Author Topic: Arnold building the "Little Blazer"  (Read 37953 times)

Offline arnoldb

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Arnold building the "Little Blazer"
« on: November 27, 2010, 04:15:20 PM »
With a couple of compressed air/steam engines under my belt, I feel like a foray into the world of flame lickers...
I have quite a couple of plans available, but for most I would require items (mostly small ball bearings) that are unobtainable locally, and hence require running the gauntlet of E-Bay and poor and unpredictable postal services to Namibia.

I nearly glossed over Phil Duclos's Little Blazer because of some of the small screws needed, but then I realised I could make them myself, so I started sourcing raw materials:

Bits of the above will go into the build.  The big round piece of aluminium is to make the base from; I can't find a rectangular piece of suitable size, and the feeler gauge will have its one blade sacrificed for the valve spring.

The build was actually started last Sunday; I milled the big round bit of aluminium down to form the rectangular block from which the engine base is to be built  First roughed  it out to a rectangular block:


Measured and marked up final dimensions:


Finally down to size and as square as I have ever gotten anything...:


Then I calculated and marked out the bit that has to be faced off at a 20 degree angle.  Nothing fancy; just some trigonometry to calculate offsets, and draw a line.  I used the height gauge on the mill vise to check that I clamped up the block at the required angle:


And faced off with the flycutter:


I used a small file to de-burr the cut edges while still clamped up, and then used an obsolete needle valve chucked up in the dremel chuck adapter to locate the one corner as accurately as possible by eye; Mr Duclos used a wiggler's needle for this step:

The mill's x and y dials were zeroed at this point for the next steps.

I dialled in the 12.7mm offsets needed on both X and Y and spotted the location with a center drill, then drilled about 13mm deep with a 6mm drill:


This was followed by a 16mm drill:


And finally the boring head to get the hole to 17.4mm - I used the 12-19mm telescopic gauge to measure; at the larger end of it's range, it's not entirely necessary to get its handle in alignment with the bore of a hole, as long as it's head is kept square to the bore central axis:


The boring was followed by offsetting the Y axis further to locate the position for the valve rod guide, and spotting and drilling a 2mm hole for the valve rod:  

I hope this does not bite me in the back; Mr Duclos specified a #49 drill which is between 1.8 and 1.9mm - and I decided to go for a 2mm valve rod...  It will be a bugger to turn up a bushing if needed   :lol:

Next followed some more markout; a lot of it was just to help me visualize the base and to double-check that things were still going to plan...:


More milling followed; pretty much following Mr Duclos's instructions:


The next photo was originally only intended to show how I use a square in the vise to set up a part a distance from the bottom of the vise when I don't have suitable parallels around, and accuracy is not of the greatest importance.  When viewing the photo on-screen however, I noticed some additional details with some valuable personal lessons behind it.  Original intent: I have a small flat square with a wide edge on the short end.  By putting the wide edge on the vise bed, and pressing it down with my middle and ring fingers, it is held fairly secure to the vise bed.  Then I use my thumb and forefinger to squeeze the part to the vertical edge, and tighten up the vise (The milling cutter is quite a way away from my hand and not dangerous here):

Now the anecdotes; there's three here.  
1.  Just to the right, and slightly above the bottom of the milling cutter is a scar on my hand.  That has been there for about 15 years, and the damage was done by my "small" 115mm (4.5") angle grinder.  I was making a security gate for a friend and was grinding away my (bad!) welding marks; using the hand in picture to hold the gate, and my right hand to run the grinder.  I was getting tired, and it only took a minute lapse in concentration and the cut was done; it could easily have been much worse, but fortunately not.  I have never since worked my "small" grinder with one hand only; the work gets clamped down, and both hands works the grinder.  If I feel I'm getting tired, I stop - a grinder tires one out quickly.
2.  If you follow the very top of the square from left to right, about a quarter of the way just above the edge there is a small scar on my hand.  That was done by a thin Dremel cutting disc breaking; my hand happened to be in line of the disintegrating disc.  Personal lesson learned; keep as much as possible of body and soul out of the spinning line of stones and discs - even a small Dremel needs to be treated with respect.
3.  To the left of, and below the top of the square, there's a scratch on my finger.  Shrek the African Gray parrot did that this morning; he was in a bit of a bad mood.  Lesson - animals (and people!) have bad moods; these I just have to accept in the spirit of love   :doh:

Enough digressing and back to the build.
Once again the impromptu center finder I mentioned earlier comes into play to locate the center for the rounded bottom "inside curve" of the base:

Though it looks like I'm only working to one line, there is a tiny prick mark left by the compasses when I did the last layout.  If you don't believe me, click here for a bigger photo.

A 6.5mm hole was drilled, followed by a 19mm (my biggest!) drill:

I was concerned about the big drill doing an interrupted cut, but as quite a lot of its tip had to follow the pilot hole, things went well.  The drill was still under size, so if it strayed a bit, there was not too much of a concern.

The 19mm hole was then opened up to 22.2mm with the boring head:


Up to this point, I've been fairly brutal with the workpiece - taking fairly big cuts at good rates of feed.  For the next phase I slowed down a bit, as workholding was becoming less secure.  After de-burring, I started by using a square to set the workpiece vertical to the angled face in the vise; once again using the method with the square - and - fingers mentioned earlier, with the centerline of the bore from the previous step above the vise jaws, and some old business cards between vise jaws and the workpiece to get things as tight as possible.  Then I milled down the back to meet the bored hole - as the face end is getting thin and high above the vise, I took just 1.5mm down-cuts at a time staying away from the final thickness:


The other side followed:


Milling down the "step" in the base proved problematic for workholding.  As the workpiece was getting whittled away, there were less - and more irregular - features to clamp down.  I _COULD_ have mounted my mill vise's swiveling base, but getting everything in tram would have required a lot of fussing about.  So I gambled on a "back-to-basics" method.  I clamped the workpiece directly to the mill table with thick bits of paper between it and the mill table, as well as between its top and the clamp.  Once again I used the small square with the offset base to align the face:

The single clamp point is far from ideal - but I didn't want to clamp through the bored hole in the face, as clamping there could distort it...

Then started milling away - lightly.  Several passes in Y to get to depth, offset X and repeat the Y  Part-way through:

Before I hit final dimensions, I checked with the square again - just to make sure nothing moved.  It didn't  :)

Before removing more metal from the base, I decided to drill and tap the mounting holes, as well as the mounting hole and screw-down for the retainer clip for the burner:


And tapped that lot - all M3 instead of 1-72 and 2-56; I deviated from the plans a bit for "comfort"   :lol::


At this point, and about eight straight hours from starting the day's machining, my cellphone rang.  I tried to answer the workshop electronic calculator... - That seriously meant time to pack up; I don't want any more scars.  So, no more machines, but I still wanted to do a bit more...

The base needed rounding over around the cylinder mount.  Mr Duclos does that using a rotary table on the mill.  Filing buttons would do as well, but machining was out for me at this stage, so I deeply scribed the curve using a conveniently sized bit of rod as a guide and trimmed the excess off with a junior hacksaw.  Then filed roughly to the scribed line with a big coarse file:


Followed by my favourite "smallish" file - down to the line by eye and judging "squareness" by eye as well:

Took all of 5 minutes to saw, coarse file, and fine file down; would have taken longer to turn up filing buttons!

A quick "lick" around the filed edge with some emery wrapped in the self-same rule in the next photo, and that's where I packed it in for the day:


I've actually had a very active day in the workshop; it feels like I've been to the gym from just contorting to check angles for holes and so on.  And of course, cranking the mill wheels - lots of exercise there! -  :big:

This was a bit of a marathon post; I value all questions, input and criticism!

Regards, Arnold
« Last Edit: November 27, 2010, 04:23:01 PM by arnoldb »

Offline j45on

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Re: Arnold building the "Little Blazer"
« Reply #1 on: November 27, 2010, 04:22:23 PM »
Great post  :thumbup:
I shall be watching with great interest  :bow:
Jason

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Re: Arnold building the "Little Blazer"
« Reply #2 on: November 27, 2010, 04:53:17 PM »
Hi Arnold


I looked at the bill of materials for this engine build ,,,,, it did not list a blue fluffy towel  :scratch:   :lol: :lol: :lol: :D


See you have already put the hight gauge to good use  :clap: :clap: :clap:


Rob 

Offline Stilldrillin

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Re: Arnold building the "Little Blazer"
« Reply #3 on: November 27, 2010, 05:01:42 PM »
A lot of fine work has gone into that one component Arnold!  :clap:

Love your humerous comments too.....  :thumbup:

Good luck with the rest of the project.  :D

David D
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Still modifying bits of metal... Occasionally, making an improvement!

Offline Dean W

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Re: Arnold building the "Little Blazer"
« Reply #4 on: November 27, 2010, 10:57:24 PM »
Hi Arnold; 
A lot of work already.  That one part has a lot going on.  Thanks for your usual good pics and words.
BTW, nice height gauge and boring head, too.  Nice work all 'round!

Dean
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Offline sbwhart

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Re: Arnold building the "Little Blazer"
« Reply #5 on: November 28, 2010, 01:20:01 AM »
Cracking bit of work that man  :clap: :clap: :clap: :clap:

Are you following book plans or are they available on the net ?.

Stew
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Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #6 on: November 28, 2010, 02:09:33 AM »
Thanks Jason  :beer:

Rob, thanks mate -  :doh: Must have gotten confused with a Ford Escort dashboard project; hence the fluffy towel  :lol: :lol: Wonder where I put the fluffy dice to hang from the rear-view mirror :scratch:.  The height gauge is a treat - really makes life a lot easier  :)

Thanks David - have to try and make it interesting  :D

Thank you Dean.  I love the boring head; and that one's mostly your fault  :bow:.  The home-made bits of kit are getting ever more useful - not as nice as shop bought tools, but they have character :)

Thanks Stew  :beer:.  Its from a book - "Two shop masters" by Frank McLean and Philip Duclos.  Photocopied pages for doing the metric conversion thing on and use in the shop.

Time to finish morning coffee and hit the shop again  :coffee:

Kind regards, Arnold

Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #7 on: November 28, 2010, 09:41:53 AM »
Hi Arnold, having built one of these myself and taken close to two decades to get it to run, I had to comment.  I built mine from the article in the Home Shop Machinist, which I believe is half size compared to the one you're building, have you decided what your cylinder will be made of and what you will use for piston material?  For my half inch bore model, I've made four cylinders and six pistons, using 6061T6 aluminum for the cylinder, and bronze bearing material for pistons.  The aluminum tends to score, and I can hone out the bore four or five times and sand the burrs off the piston before I have to make new of each, so when the piston stuck yesterday, when I was running it just to sort of end the day, I bored the cylinder out an extra eight thousandths or so, setting it up in a four jaw chuck and centering the bore first, and have machined a piston out of graphite, out of a spare electic motor brush in fact, and will be making the sliding valve out of the same graphite from another motor brush.  I hope to get more than an hour's total run time between rebuilds with the graphite but I've never run it in aluminum before.  I look forward to seeing your's run, I made a mess of the cam, machining it in a four jaw instead of on a rotary table, and translated numbers wrong, using a diameter instead of radius, and having a cam which was substantial the wrong profile.  As to the spring for the valve, it does not have to be strong, just enough to keep the face of the valve flat and no more spring necessary, my spring is made of a piece of copper sheet about fifteen thousandths thick, and I had to cut off all the excess and reduce the pressure to almost nothing to get the bronze slide valve friction down to almost nothing, getting my little version to run, so start with just enough pressure to keep the valve aligned and flat.  I'm looking forward to seeing the difference in getting your larger version running, versus mine, but considering only the work after I figured out all the errors I made, as they don't figure in the virtues of the design its self.  I can hardly wait to see the video, you're looking very good so far. :headbang: mad jack

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #8 on: November 28, 2010, 02:44:26 PM »
Thanks Mad Jack  :beer:  I don't know if you're talking about the same engine; I wouldn't like to build this one in half size - Well, not yet anyway; I would need some 1mm taps first!
I'm making the cylinder from cast iron and the piston from phosphor bronze; I don't have access to graphite for the piston yet.  Thanks for the pointers!

On to today's bits.

Phil specifies the clamping screw on the collar as a 1-72 cap screw; I don't have anything that small, so I settled on an M2 machine screw.  Head clearance for this screw is 4mm - and the collar is 4.7mm wide; that leaves 0.35mm either side; loads of space   :lol: - as long as I could pull it off accurately.
I used the sharp pin to locate the edge of the vise jaw on Y, zeroed it and dialled in 2.35mm offset.  Then I located to the center scribed line for the X and locked that:


Then with a 4mm center-cutting slot mill, very gently bored down to 1.5mm above the depth mark:


Next followed a small center drill - just a shallow hole with its tip:


That was a guide for the 1.6mm drill that followed - about 10mm deep for tapping M2:


A 2mm clearance drill followed; just 2.5mm deep, and then I tapped the holes - still in position, but with the collet holding the small drill arbor loosened to allow the arbor to rotate and slide in it.  I just chucked the tap in the drill arbor and twirled the shaft with my fingers to tap the hole; it does not take a lot of torque to thread M2!:


As a final step, I slit the collar with a 0.5mm slitting saw:


Some more layout followed:


I used a 10mm mill to clear the big bit of excess away - just by eye to the lines, making sure that the bottom met the curved section in the base nicely:


To mill out the section between the two bearing columns, I had to revert to a 6mm mill.  The 10mm is too big here, and I thought I had an 8mm long series.  Well, so much for "thought"  ::) :

  :doh: Notice the ding on the top of the collar ? -   :( - I forgot to check clearance for the collet chuck and left too short a bit of the cutter sticking out, so I ran the collet chuck into the collar...  Fortunately not to bad; the chuck lost some black off it's closing nut, and the ding was very shallow and easy to file away.  I just hate that sudden extra "grrrr" noise!

Then I milled the back end to 10 degrees as per plans:


For laying out the center line for the crankshaft, I needed a plug turned up to fit closely in the collar.  This calls for a "scrap" bit of "something - but I couldn't find any, so I used a good bit of aluminium.  It was really nice to get back to the lathe for a change   :D :


That piece was then just parted off and clamped up in the base collar.  Phil recommends clamping the base to an angle plate for the next step; I don't have one, so bodged it by holding the piece against a square  with the base edge firmly lying on the glass plate.  Then get the height at the top of the plug, subtract its radius, set the height gauge to that, and scribe the center line on the one column:

It looks as if the base is not sitting with it's one edge flat on the glass plate in the photo; that's an optical illusion.

The other "crossing" center line is easily marked from dimensions, and this is the result:


The piece was then set up squarely in the mill again, and the axle bearing holes drilled at 2.9mm for reaming out to 3mm later.  At this point it was 14:00 and my elderly neighbours like to take a Sunday afternoon nap.  Their bedroom is very close to my shop, so I shut up with the machines for a while, and brought out the small needle and riffler files to clean up the base a bit - after I used a larger file to round off the one sharp edge and the tops of the bearing columns:


A while later, and after some 320 emery followed to get a brushed finish, I ended up with this:


Well, while posting up I noticed it's not quite good enough yet; the one bottom mounting hole came through the base between the pillars   :doh: - so that needs to be fixed.  And as always, one sees some more places that requires finishing off - the camera is pretty good at showing those up!

Once I heard the neighbours were awake, I started off on the cylinder.  A bit of 30mm cast iron - faced off and center drilled:


Then turned down to 1", and cleaned up a bit with emery:


The neck turned down and a trial fit to the base; it had a bit of a step at the back that needed further relieving, so it appears a bit short:


Turning the fins on the cylinder was a no-brainer; much to my surprise   :ddb: I thought I'd have to make a turning bit, but found one among my assortment.  BONUS - it was already sharp and suitably profiled for cast iron :)  And its tip was 1.6mm thick! - Well I needed 1/16" - 1.59mm. That half a thou won't make much of a difference  :coffee:  And another bonus; my lathe's leadscrew is 8 TPI, so one turn per fin; no messing with numbers!  Fins started:


And done - 15 minutes later:

It took longer to get in there with some emery to get a bit of shine showing up in the bottom of the grooves than it did to groove them  ::)

Then I bored the cylinder...  I'm not entirely happy with the finish inside, so I suspect a lot of lapping will be required later.  Not sure though, as cast iron is deceptive.  Brass and aluminium will machine to a mirror finish indicating that it is smooth, while cast iron can be very smooth and still look dull...:


I parted off the cylinder .5mm over length for clean-up - then chucked it with some paper to protect the finish on the fins, and cleaned off the back side:


The cylinder to this point; I quit while I was ahead today  ;) :


And assembled thus far:


I don't think there will be any progress during the week; so most likely next weekend only.

Thanks for checking in!

Regards, Arnold

Offline raynerd

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Re: Arnold building the "Little Blazer"
« Reply #9 on: November 28, 2010, 03:23:14 PM »
 :bow: :bow:

Amazing! I`ll be waiting for the next instalment...excellent job.

Offline Stilldrillin

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Re: Arnold building the "Little Blazer"
« Reply #10 on: November 28, 2010, 03:45:18 PM »
That was another good day's work Arnold!  :clap: :thumbup:

David D
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Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline sbwhart

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Re: Arnold building the "Little Blazer"
« Reply #11 on: November 28, 2010, 04:00:09 PM »
Great bit of work Arnold and really well shown.

 :clap: :clap: :clap: :clap: :clap: :clap:

Thank you.

Stew
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Offline Brass_Machine

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Re: Arnold building the "Little Blazer"
« Reply #12 on: November 28, 2010, 07:42:46 PM »
Finally caught up with this one. Very nice work Arnold. Love the side comments  :lol:

Gonna be watching this one.

Eric
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Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #13 on: November 29, 2010, 11:03:47 AM »
Thanks Lads; much appreciated :beer:

Kind regards, Arnold

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #14 on: December 04, 2010, 05:49:57 PM »
Finally, some more progress  :)

I clamped the cylinder lightly (to prevent distorting it) in the mill vise on top of one of my crude parallels.  Some cardboard serves to both protect and to ensure a better grip. Then I used the height gauge to find the top, made a note of the reading, and marked out a line to depth for milling away the port face:

Of course, I first cleaned the mill table well of any swarf in the area where the base was located before doing this!

Then I milled away the port face.  As the cylinder was clamped lightly, I milled away the face in small increments; 0.5mm max depth of cut a t a time:

All the passes were done in line with the cylinder bore to prevent it trying to rotate in the vise.  When I got close to the scribed line, I checked again with the height gauge, and fed in the last required amount using the Z handwheel scale.  As this pass was very light, I opted to do the last cuts perpendicular to the cylinder bore, as it would make it easier to remove the tooling marks later.  As a final step, I also milled the clearance flat for the valve pushrod.

I very lightly marked out the location and size for the valve port with the cylinder still clamped:

Very lightly, as I didn't want deep scratches to have to remove later on!

I went to my engineering suppliers this morning, and returned with a couple of new bandsaw blades and some milling bits, and while there something kept tugging at my mind and wouldn't quite surface.  At this point it did  ::) - I needed a 3mm milling cutter for the valve port, and I didn't buy it... 4, 6, and 8 mm, but no 3mm   :doh:  By then the shop was closed as well  :( - So I settled on using the 2mm cutter I have, and milled the port - widening it to 3.2mm with a couple of edge passes:


While milling the port another thing raised its head...  I'm a pretty easy going person, but one thing I HATE is squeaks.  And the mill's y-travel handle had started to squeak - deep in the inside   :bang:.  I removed it, and tried getting some oil in there, but it just wouldn't go down and stop the squeak, so, on to the lathe, and drilled a hole into it from the other end:

A drop of oil in there, and squeak sorted   :ddb:  It's a pretty crappy plastic handle, so I just might make a nicer metal one in future.

Back to the build...  I have the princely sum-total of 2 slitting saw blades; one 1mm thick, the other 0.5mm thick, and fortunately both of the same diameter.
Ganged together on the slitting saw arbor, I could slit the head fins with a 1.5mm gap instead of the 1.6mm called for in the plans.  Phil's plans actually calls for slightly thinner fins on the head than on the body, so this is fine; except that I made a slight miscalculation, and instead of keeping the original spacing called for and making the fins slightly thicker, I decreased the spacing to keep the fins to dimensions...  Silly me; that left the bottom fin a bit on the thickish side   :hammer::


Next I removed the cylinder from the mill, and flat-lapped the port face using different grades of emery on my glass "surface plate" to get rid of the tooling marks, making very sure that I kept it very flat.  It wasn't a lot of work; just a few strokes each on 320, 600, 800 and finally 1200 emery, and ended up with this:

This is one of the nicest surface finishes I've ever gotten on cast iron; and now I know it is possible to get CI to a near-mirror finish!

On to the piston, and for this, I brought out the best in my minimalist arsenal of tools; my prized Moore & Wright micrometer and Mitutoyo telescopic gauges.  My one sister gave me the M&W many years ago as a gift, and I have never used it much.  The set of telescopic gauges I bought last year in a "Cash Converters" shop for the then equivalent of US$10.  And they are not fakes... Once in a while one gets VERY lucky  ;D.  I'm digressing   :med:
I set the telescopic gauge to the cylinder bore, and used the micrometer to check the reading; three times over to make sure I had no errors, and then another couple of times just to be 100% sure.  I did pick up a slight tightness mid-way along the cylinder bore using the gauge; that's a problem to sort out later:


On to making the piston; I turned the piece of phosphor bronze I have for it down to just over size on the OD, and then drilled and bored the ID to the required size:


Then I finished off the OD of the piston to 0.005 mm (that's a quarter 'thou give-or-take) smaller than the bore of the cylinder as measured earlier - using the micrometer to check.  I have gotten into the habit of working accurate to 0.01mm on my lathe; this was really pushing the envelope for me, so I used my HSS cutting bit as sharp as I have ever been able to hone it, and I was careful to keep a consistent feed while doing the cutting.  I used the compound slide set over to 30 degrees to dial in the final cuts; there's quite a bit of reading material on using this method available.  Then I parted off the piston; the threaded rod in the tailstock chuck is just to keep it from ending up in the swarf heap:

  :bang: :bang: I'd done well up to now, but forgot one of the most important things I'd learned while making and then parting off pistons   :doh: - The parting off raises the metal next to the parting area  :coffee: - and I didn't pause to clean that up while parting, or even better, do a partial parting before turning the piston to size.

Fortunately I did leave the piston slightly over-size, and would need a mandrel to finish it off together with the cylinder bore.  I left the "left-over" phosphor bronze I used for the piston in the 3-jaw chuck and removed the chuck from the lathe; if needed be I could make another piston from that.  Then I mounted the collet chuck, shoved a bit of 12mm aluminium in it, and turned it down to a light slip-fit for the bore of the piston.  I then used a center drill on the end of it, to allow clearance for the revolving center, and slided the piston over the aluminium, and used the center to nip it up in place.  Then I used a rule with emery to get rid of the high spot on the parted-off side of the piston:


Next I removed the piston, drilled for and tapped an M2 thread into the aluminium arbor, and screwed down the piston on it:

I mixed a couple of drops of thin oil (3-in-one) and some metal polish ("Brasso"), covered the lathe ways with absorbent paper, and coated both the piston and cylinder bore with this mixture.

PLEASE DO USE GOOD SENSE IF YOU TRY TO DO WHAT I DESCRIBE IN THE FOLLOWING SEQUENCES - note I say "good sense" and not "common sense" - last of which is unfortunately worthless nowadays IMHO.  With the lathe running at a low speed (on my Myford I chose back-gear medium speed), I started lapping the cylinder onto the piston using the oil-and-polish mixture - with the cylinder lightly gripped in my right hand and moving it up and down the piston, and my left hand on the lathe clutch to stop the lathe if something went wrong.  Don't try to use just metal polish; it dries out and will tighten up; the oil added to the mixture helps to lubricate it.  And if things tighten up, release your grip on the cylinder first, and then stop the lathe. 

There was not a lot of lapping required, but the tight spot I mentioned earlier in the post while measuring the cylinder was still there (easily felt by a tightness requiring a bit more holding torque when moving the cylinder over that point), so I chose a quick-and-dirty fix for that.
A proper lap would be the best way to go, but I sawed a slot on the mandrel to hold some folded up 800 grit emery trimmed to size to lightly fit the bore of the cylinder when wrapped around the arbor.:


I shoved the cylinder over that, moved it over to where I'd judged the tight spot to be, and started the lathe, once again holding on to the cylinder with my right hand and moving it side-to-side a little bit.  Just a couple of rotations of the lathe to run that tight section in a bit, and I was done with the more dangerous stuff.  A video to break the monotony, and show how the piston fits the cylinder:

OK - End of risky sequences  :)

Next I started on the wrist-pin bracket.  This one called for aluminium as well - I'd originally set out brass for it, but with the weight of moving parts on this engine playing a major role, I changed my mind and used aluminium.  I have some 5mm aluminium rod scavenged from old UHF TV antennas, but that is horrible stuff to machine, as it is extruded soft ali.  As I have been extravagant on wasting aluminium on this build thus far, some more wouldn't matter anyway, so I flipped the bit of 12mm I already had in the collet chuck from doing the piston to get at the un-machined end, and turned it down:

I just used the step-turning to prevent flexing; though the whole lot could have been done in one go.  The tip is down to the correct size, with some room for machining left on the thicker bit.

The front bit needed to be slit for the connecting rod - and with some more machining in the lathe to come after that, I took the plunge, and unscrewed the lot - chuck-and-all from the lathe, and lightly clamped the collet chuck in the mill vise.  When I built the collet chuck, I left it chunky, so I don't think it will distort from getting used in this rather unconventional way:


Then I slit the ali for accepting the connecting rod - specs show 1.6mm, but I did it at 1.5mm:


And cross-drilled for the wrist (gudgeon) pin:


Back on the lathe again, and I just used the rear parting tool to trim the lot down to length, and with a 2mm diameter back end - to get threaded later:


After final parting off, mounting in the collet chuck to thread the shaft M2 with the tailstock die-holder and a bit of clean-up, the wrist pin bracket was done:

 :ddb: I was surprised; this is a fairly small part and it came out OK without any hassles!

The valve pushrod followed; nothing difficult; just a bit of 2mm bronze brazing rod - threaded M2 at one end:


And with a flat filed free-hand on the other end for a grub screw (set screw):


One valve push rod done:


With a bit of time left in the shop, I started on the connecting rod - marked out some ali:


Drilled for the big- and small ends:


And milled to size on the accessible sides:


I used a slitting saw to trim it off the parent stock:

When it started to wiggle around - JUST before it was fully parted off, I stopped the mill, and broke it off by hand.  Saves one from having to search for a part tossed across the workshop on final cut-through  :lol:
Some filing was required; I could have done more to it on the mill, but setting up sometimes takes more time and energy than a bit of judicious filing:


Connecting rod done; I'm not entirely happy with it as I over-filed some spots (So much for "judicious" filing  ::)) - but it should do for now:


For anybody that reached reading this point in the post, -   :bow: Darn, I admire your persistence, as I was starting to bore myself!

In a nutshell, the results of today's efforts:


I hope to get a bit more done tomorrow   :)

Regards, Arnold

Offline Brass_Machine

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Re: Arnold building the "Little Blazer"
« Reply #15 on: December 04, 2010, 06:04:19 PM »
...
For anybody that reached reading this point in the post, -   :bow: Darn, I admire your persistence, as I was starting to bore myself!

...

I read it all, and quite frankly enjoyed it. Great work!

Eric
Science is fun.

We're all mad here. I'm mad. You're mad.

Offline cidrontmg

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Re: Arnold building the "Little Blazer"
« Reply #16 on: December 04, 2010, 07:39:26 PM »
...
For anybody that reached reading this point in the post, -   :bow: Darn, I admire your persistence, as I was starting to bore myself!
...

I read it all, and quite frankly enjoyed it. Great work!

Eric

+1, and not for a second was I bored! Very enjoyable reading all the way. And lovely work again, as usual. A flame eater is very near the top of my projects list. Watching enthusiastically how it should be done, although Iīll never be able to.
Olli
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Offline sbwhart

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Re: Arnold building the "Little Blazer"
« Reply #17 on: December 05, 2010, 02:14:32 AM »
Great read and job Arnold  :headbang:

Thanks for posting.

Stew
A little bit of clearance never got in the road
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Location:- Crewe Cheshire

Offline Trion

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Re: Arnold building the "Little Blazer"
« Reply #18 on: December 05, 2010, 03:19:47 AM »
Great post Arnold, looking forward to the next one! :clap:

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Re: Arnold building the "Little Blazer"
« Reply #19 on: December 05, 2010, 04:00:59 AM »
Finally, some more progress  :)

For anybody that reached reading this point in the post, -   :bow: Darn, I admire your persistence, as I was starting to bore myself!


I hope to get a bit more done tomorrow   :)

Regards, Arnold

Arnold.
Not the least bored. Full of admiration.  :clap:

Read every word, and perused every pic. Though, I had to have my breakfast first.... .

Looking forward to today's instalment!  :thumbup:

David D

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Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline shoey51

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Re: Arnold building the "Little Blazer"
« Reply #20 on: December 05, 2010, 05:00:54 AM »
very enjoyable read :thumbup: :clap:

Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #21 on: December 05, 2010, 10:35:26 AM »
Hi Arnold,  I finally read your post beginning to end and have a couple of comments which are appropriate.  First off, you are doing a very fine job, both in the machine work, and in the posting, like so many others have said, I'm not a bit bored, I just feel like maybe you should have more friends to present gifts for the improvement and expansion of your "kit".  The one I built is the same size, I made an assumption, having read other builds that were done "by the book" rather than out of the magazine, as I did, and they were twice the size I, and now you, are building.  Mine is essentially identical, except not metrificated.  The plans called for aluminum for the cylinder, and you did very well to ignore that and use iron, I suspect you will have far better an engine for that choice.  I would suggest you look at the thermal expansion factors of cast iron and compare it to the bronze you are using, and multiply the approximately half a thousandth clearance necessary, by the difference, to ensure the piston does not expand beyond that clearance.  In Machinery's Handbook, it lists cast iron at .0000065 unit length expansion per degree, with bronze listed at .00001, making just short of twice the rate of expansion.  I suspect a full thousandth of clearance will give a working clearance of less than half a thou when up to temperature, which is plenty with graphite as lubricant.  If you have any problem with the piston sticking, it could just as well be made of cast iron from the same source, and would not be significantly heavier if you keep the walls thin, as well as the top, of the piston, that is.  I don't believe you will need to use graphite for a piston as the iron won't gall the way aluminum does.  Having read through your post, I'm half tempted to turn an iron cylinder and a piston to go with it, and be done with the aluminum cylinder altogether.  I think you have eliminated all the problem factors I've already been frustrated with over a period of twenty years since I built mine, and since I got it running, only a few short months ago.  I don't wish to impose on your log, but as you, I did not have much in the way of tooling when I built mine, and I used a four jaw chuck instead of the rotary table I didn't have, to turn the cam, and I used Mr. Duclos' numbers, forgetting I was in a different position, and my cam came out with a substantially wrong profile, because I used a radius distance from center, rather than diametral, it seemed to be the same thing at the time, but gave a profile very much wrong, and kept the engine from running, along with other issues.  If you use a four jaw to form the cam, make sure your indicator is showing the full diameter offset, and not just the radial offset, as I did.  I expect you will have a very good running little engine in the very near future, and I'm looking forward to the video, the one with your piston and cylinder is good and shows a very good clearance and fit and should work very well.  I have a cheap tachometer off e-bay, put a tab of reflective tape on the flywheel, and was getting about 2500 rpm easily with fresh pistons and cylinders, and I expect you will get similar results without the galling, just needing cleaning on occasion as the drop of oil for the crankpin will end up in the cylinder.  I am very pleased to see this engine being built again, with differing thoughts, and in my opinion, better materials than I used.  I have seen it built and run with the engine half sized, with a bore of a quarter inch, on u-tube sometime in the recent past, so they will run even smaller, as well as seeing many made in double size, with about an inch bore.  Looking forward to seeing it run soon, great build and fine build log :poke: mad jack

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #22 on: December 05, 2010, 05:02:14 PM »
 :) Thank you very much Eric!

 :beer: Olli.  I'm not sure if this is the way it should be done either; I'm just doing it.  And having seen your Stirlings, you should have no problems at all getting a flame licker going  :thumbup:

Stew, Thanks very much mate :D

Thanks Trion  :beer:

Cheers David D  :beer: - I hope you had a full English :thumbup: - nothing like lots of eggs and bacon !

Thanks for checking in you Shoey51!

Thanks Jack - I don't like to call you Mad Jack by the way ;).  There are many members here on MadModder who have helped me a LOT - not through giving me "kit" but through sharing knowledge and supporting me - and that's something all the kit in the world can not make up for.  A load of fancy kit without knowing the basics of how to use it is just that - a load of kit.  I'm striving to use the bits I have, and with the generous help received,  learn to use them well.  Then, as I'm expanding my available bits, I'd just be in a position to use it even better.  Thanks; I did consider the materials I have available for this build - that's why I settled on the CI cylinder.  I'll give the bronze piston a go - if it does not work, then I'll re-do it in cast iron. The influences of heat in an engine is an entirely new experience for me, so I have a lot to learn from it  :)

I didn't get as much done today; which makes for a shorter post for a change - saves you chaps from eye strain :lol:

Following Mr Duclos's instructions I turned a piece of aluminium stock down to the outer and core diameters for the combined crank web/cam:

This was followed by drilling the center 2.9mm and reaming it out to 3mm for a fit on the crankshaft.

Reading through the steps required to machine the cam on the mill and rotary table, it seemed (and was!) a good idea to make up something that I could clamp in the mill chuck for centering purposes.  Seeing as the crank shaft would be ideal, I cut that off from some 3mm music wire I have.  The Dremel and a cutting disc works great for this; the music wire instantly blunts the junior hacksaw blades I have  ::) :


I then centered the rotary table to the mill spindle, clamped up the workpiece in the small Myford milling vise, and used the shaft chucked up in the small drill adapter to center the workpiece-with-vise combination on the RT - with the RT set to 0 degrees.  When I built the RT I took great pains to make sure that the T-slots were exactly on 90 degrees apart and the one on 0 degrees was just that.  So I used the edged square shown in a previous post with the edge located in a T slot to set the vise square, and clamped a bit of flat iron down against the top of the vise to keep the reference Phil mentions in his write-up:


Then I just followed Phil's instructions and dialled in the offset needed on the Y axis, moved the vise against the clamped down reference bar, and used the shaft-in-chuck to locate the final spot to clamp down the vise.  Then milling the cam profile was easy - though I did get the milling depth slightly too deep and ended up scarring the lower workpiece face   :doh::

Fortunately the scar is not as bad as it looks; it's mostly a burr... That 6mm milling bit is getting a bit blunt!

It was easy to set everything back to "0" after milling the cam, and then to dial in the 43 degrees counter clockwise on the RT needed, and then dial in Y to depth to locate, drill and tap the connecting rod screw-hole:


The workpiece was then removed from the RT, and parted off from the parent stock on the lathe.  I wish I'd read the instructions trough to the end again before doing this, as I could have saved myself a lot of work later :Doh:.  Phil mentions at this stage of his instructions that you have to leave "sufficient" extra stock on the back of the workpiece to later clean up...  So I left 1mm extra and parted off...

A bit of a diversion followed; the parted off workpiece had to be clamped to the RT again to mill out the webs.  I do not yet have a good selection of bits 'n bobs for clamping to the RT; my mill's clamping kit is waaay too big.  The RT's T slots are the same size as my lathe's, and I always just used 6mm cap screws of appropriate length and home-made T nuts to clamp things on the lathe's vertical slide.  I couldn't find a suitable length cap screw today, so I had to use a bit of high-tensile threaded rod.  One thing I did not do in my more inexperienced making of said home-made T nuts, was to prevent anything screwing right through them - as an arbitrary length of threaded rod would do, so a quick-fix was called for.  A chisel, a hammer, a T-nut clamped upside-down in the  big bench vise, four quick blows, and the result:

Now a rod or bolt won't screw through past the end   :ddb:

I laid out the back of the workpiece, and an odds 'n ends clamping session on the RT followed, using the shaft-in-chuck to make sure the shaft-hole was on center:

No super-accuracy was needed for this step, but parts do look better if accurately made, so I took a bit of time getting it just right.

Then I milled out the web; 6 degrees offset  On the RT for each side, and to the lines:


To drill and tap the web for an M2 set screw, I clamped it in the mill vise, and used a bit of 2mm brazing rod chucked in the small chuck to locate the hole:

There was not enough clearance for a center drill to get in there, so I used the 1.6mm tapping drill to make a little dent to act as starting point. With the mill stopped, lightly press it down on the workpiece, lift of, turn the chuck 180 degrees by hand, press down slightly harder, lift off, turn the chuck 90 degrees, lightly press down again, turn another 180 and press down slightly harder again.  Lift off and start the mill, and drill the hole; the small drill bit will hit the correct spot using this method most of the time without wandering, as the light dent in the workpiece serves as a center mark.
I drilled the 1.6mm threading hole using this method, and then tapped it M2 for a set screw.

Phil notes at this point to chuck up a suitable rod (or turn one down) to 1/8" (3mm in my case) and make a flat on it, and then mount the workpiece on it, locking it down with a set screw through the threaded hole made in the previous step, and to face off the the back of the workpiece to get it to an overall thickness of 1/4" (6.35mm).  I tried that and it was no fun at all...  This is on an interrupted cut with a puny screw trying to hold on...  And remember I left 1mm extra to face off  :Doh:.  When the workpiece came loose from the shaft the second time, I went to plan B - which was to wrap a bit of paper around the cam, chuck it up in the 4-jaw chuck by the cam; just roughly on center, and face it off to thickness:
.
Had I read the instructions up to this point, I would have parted off to just 0.01mm over size initially, and just removed the toolmarks on a bit of emery; that would have left the workpiece perfectly on size without a lot of additional faffing around.

After a bit of filing to round corners and some work with emery to clean up, I ended up with this:


The crank/cam took quite a while to make, as I expected, so shop time was running out for today.  I did manage to get some additional small bits made though.

The crank pin bushing - 2mm ID, 2.48mm OD and 4.35mm long:


Followed by a 2mm bolt from some 1/8" brazing rod, and a little retaining washer:

I will most likely re-make the bolt from silver steel; it just occurred to me that it will experience quite big forces on it when the engine is running!

At least, things are starting to resemble an engine now :D:



Regards, Arnold

Offline Dean W

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Re: Arnold building the "Little Blazer"
« Reply #23 on: December 05, 2010, 06:14:57 PM »
Very nice work, Arnold!  The crank/cam is deceptively complicated, and you went right at it, just like a machinist.  : )
I've read all your writing from the beginning, though some days don't have time to post.  This is another fine write-up
with you as the author.   Entertaining and educational.

Something for later, (next time you make T-nuts), if you use an old ball bearing or 60 deg center, you can flatten the bottom
thread in the nuts with a good whack of a hammer.  Works well, and leaves the bottom of the nut smooth.

Dean
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Offline NickG

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Re: Arnold building the "Little Blazer"
« Reply #24 on: December 06, 2010, 06:55:23 PM »
Hi Arnold, just found this, not read it yet but posting a quick reply to remind myself and say well done - your work looks great so far, I love these engines.  :thumbup:

Nick
Location: County Durham (North East England)

Offline sbwhart

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Re: Arnold building the "Little Blazer"
« Reply #25 on: December 07, 2010, 01:26:46 AM »
Looking good Arnold you make real quick progress  :thumbup: :thumbup:

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #26 on: December 07, 2010, 07:46:30 AM »
Hi Arnold, It was good to see the crank being machined according to the instructions, and from the looks of the cam, it's right, and in keeping with my last post, I still think you will do just fine with the piston you have, and you definitely made a good choice in your deliberate decision.  It looks like you're right close to being ready to start it up, just a few more pieces.  Very nice work with the log as well, very easy to see your work.  Now I'm really looking forward to that video  :poke:  The "Mad Jack" came out of the fact I used to run when I was a Marine, and did so both in the morning, with my Marines, and at noon, for my own pleasure, hence the "mad".  Just a couple more pieces..... :) I really want to see how that cylinder works out for you  :nrocks: mad jack

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #27 on: December 07, 2010, 12:31:25 PM »
Thank you very much Dean : ) I don't know about "just like a machinist" yet, but I must admit that I'm pleased with the progress I've made in learning to use my machines.  I have a lot to learn still, but that's all part of the fun!  I forgot completely about using an old ball bearing for whacking down the threads on the bottom of the T-nuts - must have been the heat-of-the-moment ::).  The last couple of times I made T-nuts, I actually just didn't tap them all the way through with the last tap in the set.  It might be better to tap them through though and then flatten the last thread; I think the bolts/rods screwed into them will stop more solidly and not try to seize up as much in the taper thread left by not tapping all the way through...

Nick & Stew, thanks !

 :lol: OK Mad Jack - you won me over with your explanation ;) and thanks!  There's still quite a couple of small parts to make, and these take the most time  ::)  The cam fork (and I have been known to end up with a "forked" fork!), roller wheel, valve, valve plate, valve spring, M2 set screws, -bolts, and -nuts and of course the base, flywheel and burner.  Winding the spring from an old guitar string will most likely require a jig as well and I have to make the slitting saw to slit the valve face (or cheat a bit!).  So I'm only about half-way there!

By the way, does anybody have a suggestion on "soldering" the valve plate to the valve ?  Mr Duclos does not specify anything beyond "soldering" it - would ordinary electronics solder (the old 60/40 type with real lead and tin) do the job, or is it better to silver braze it.  I don't know how hot the valve gets in operation; maybe the solder would melt?

Kind regards, Arnold

Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #28 on: December 08, 2010, 10:47:14 AM »
Hi Arnold,  I'm glad the name thing is cleared up, but I answer to almost anything, as far as soldering, I have taken a worn out valve and soldered a piece of fresh brass to its face, and it lasted a few minutes and the solder was melted.  It was Sn63 Pb37, technical grade electronics solder.  In making the valve, Mr. Duclos suggests making a one tooth slitting saw, and putting a slot a few thousandths wider than the thickness of the spring, and having a radius at the bottom of it, matching a radius put on the end of the spring which is bent to be at right angles to the cylinder.  I used an actual slitting saw I had, fifteen thousandths thick, and it has worked well, however I have seen several other engines of this design where the builder simply bent the "spring", which in my case is a piece of brass shim stock, such that it was held flat against the valve face, with a very slight amount of spring pressure, as there is substantial surface area to be reckoned with, friction wise, and those engines seem to perform better.  With your cast iron cylinder, I expect a bronze valve would work fine, but it is a bit of work to cut out the area around the raised section in the middle where the slitting should be, and then cut the plate its self off the bar it is made on the end of, and then face off the cut side afterwards.  I've done it about three times and it's much easier the second time, but I wished I'd have made the valve just out of the flat of the spring, or, now with my experience with aluminum cylinders, made it using similar technique, but out of a motor brush of graphite, which would be both lighter and non-galling on the aluminum.
   To make the spring its self the valve, I'd go with a piece of brass shim stock about fifteen thousandths or so, cut to width a bit wider than the port, leaving extra length, clipping the corners on the other end and rounding it out, then bending it at just less than ninety, holding it against the valve face and finding where the valve rod will hit the bent up end, drilling it with the barest of preference to the outside, to allow for some spring force against the cylinder, then setting it up with two nuts centering it in the threaded area of the valve rod, and cutting off the excess about twenty thousandths past the outer edge of the port, then removing the shim stock and radiusing the corners by the port, and putting a radius on the end edge so the tip of the valve spring won't catch in the opening of the port, as it slams shut, as the cam is designed to do.  From there, it is a matter of adjusting the nuts to ensure the valve completely seals the port, but has no excess travel which would reduce the open time of the port.  To do the valve as Mr. Duclos specified would be to do essentially the same thing, except a couple of millimeters past the bend for the valve rod, you would have to bend it away from the valve face, with about a forty five degree angle, then bend it parallel to the port face for a short distance, and then bend it sharply in a right angle, to return back to the port face, and cut off the end, so it just about touches the face, and then put a radius in the end, to hold the bronze valve and keep it from sliding down under the influence of gravity, (it's the law) but having just enough spring to hold the valve plate in place while running, while not enough pressure to insert too much friction in the valve action.  With such a valve, a piece of spring wire could be used with a loop for the double nuts for adjusting the valve opening, and with two ends bent at right angles, and cut off to insert in two shallow holes in the valve, not penetrating the valve its self.  I will try to find a picture of an engine of this sort with the flat valve made straight out of the shim stock or spring steel if I can.  :jaw: mad jack

Offline Gerhard Olivier

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Re: Arnold building the "Little Blazer"
« Reply #29 on: December 08, 2010, 12:53:31 PM »
Nice job on the engine Arnold

And congrats on the Engine of the month!!!! :thumbup:

Gerhard
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Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #30 on: December 09, 2010, 10:50:59 AM »
Thanks Mad Jack - I thought the electronics solder would melt...  So it's silver brazing for me then; I'd better find the pencil torch!  I'm for once trying to stay as close to the original plans as possible on a build  ::)

Double thanks Gerhard  :beer: - The engine of the month thing was totally unexpected!  Feels a bit funny to see the photo sitting there every time I look in on HMEM...

Tomorrow's a public holiday here in Namibia, so I should get some more done on the engine  :dremel:

Kind regards, Arnold

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #31 on: December 10, 2010, 01:48:47 PM »
Today's shop time  :)

First order of the day was the cam fork - a straight forward milling job to get to size:


And after sawing off from the parent stock, drilling and tapping and a quick rub over emery:


Then I made the cam roller:

This is the second one I made; the first one went on a flying trip while I was trying to clean up burrs - I just heard it hit a wall and something metallic; didn't even see where it went...  At least the shop monster got a bit to eat   :coffee:

A little M2 bolt followed to act as roller pin - just some brass threaded rod turned down, threaded, and the head section filed to a hex while on the lathe:


Then I had to re-make the cam roller again  ::) - I made the original one 3/16" and when I started putting things together, it looked way too small.  Misread the print; it was supposed to be 5/16"!  Parting off on the lathe no longer intimidates me like it used to, but on these smallish bits I always end up with quite a big burr that have to be removed from the parted face afterward.  I tried something different for this one: before drilling the center hole, I parted it to just under the drill size, then center drilled and drilled the hole to size.  Works a treat; I ended up with the roller sitting on the drill and only a very light burr:


The finished fork with the roller installed on it:

While posting, I happened to notice this photo was the 2000th one taken with my current digital camera - and I've only had it for about a year.  A quick calculation, and it has paid for exactly half of it's purchase price in saving on having 35mm film developed!

The valve plate needs a 0.28mm slot cut in it, and Phil very kindly describes making a small slitting saw for the job.  I deviated slightly from his design, but used the same principle.  First some 12mm silver steel turned down on the lathe; the section closest to the chuck I just cut using successive parting cuts with the rear toolpost, and then slowly and lightly faced the front section down to obtain the correct width.  A very sharp HSS toolbit made this a no-brainer though I was a bit apprehensive of machining to such a thin width initially:


Then some delicate-but-rough-looking milling on the rotary table followed.  The first person to spot the boo-boo I made has a choice of one of two prizes:

The prizes to choose from are a) an under-water hair dryer or b) a steam loco catching kit consisting of a bag of charcoal and a bear trap  ::) - UK members don't qualify for option b though, as it would just get used to heat shops  :lol:
Fortunately, my mill can run in reverse....

I very gently filed cutting clearance behind the teeth, and then hardened the cutting teeth by heating red hot with a blowtorch and dunking vertically in oil.
For this cutter, I didn't bother to temper afterwards; it did not come out quite as well as I would have liked, so will most likely be a single-use one for brass only.

I then started work on the valve plate.  Some brass, carefully milled down to size:


And then used the cutter made earlier to slit the top - worked a treat  :dremel: :


After using a bigger slitting saw to separate the valve plate from it's parent stock, it was just clamped by the protrusion in the middle, and milled down to the correct thickness of 0.3mm:


A bit of clean-up, and careful flat-lapping of the face (to remove toolmarks and get it really flat and smooth) followed - and that's the valve plate done:

I noticed something interesting while doing the flat-lapping.  Normally I can see the lapping starting to take effect very slightly on the outside edges first, but on this one, it started in the middle and took quite a bit of lapping to reach the outside edges...  I think while milling the bottom flat, the milling cutter bent the thin outside edges slightly down.  Just a tiny detail to consider in future....

At this point my woes really started...  I had the bit of 0.1mm feeler gauge to make the valve spring plate from.  Mark-out went easy and a pair of tin-snips made short work of trimming it down.  Then I had to consider drilling a 2mm hole in it to fit on the valve pushrod.  Thin plate and drills don't go well, so I sandwiched it between some aluminium scraps clamped with a toolmaker's vise:

Drilling went well, but I could feel that this feeler gauge plate was something different; it was tough to get through with the drill...

When I tried bending it, this happened:

  :bang: - this steel plate does not like bending...

That was the only bit of 0.1mm plate I had... The off-cuts are too small to use, but I used the busted bit to do an experiment; I tried bending it around some 1mm rod, and that went OK:

Except, when I tried the minutest adjustment after the original bend, it promptly snapped again. 

I tried bending it while heated red-hot with the pencil torch; same result.  I had a closer look at the feeler gauge set this came from, and it's made by Gedore in South Africa - pretty good quality kit - hence good quality, but frustrating, steel in this case.  I thought it was a cheapy set of imports; what a waste of good tooling.  At that point I decided to call it a day and have a good sleep over what to do next for the valve plate spring.  Besides, it had started raining here and rain is best appreciated sitting on the stoep (porch) with a very cold beer in hand.

Regards, Arnold

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #32 on: December 11, 2010, 01:28:08 PM »
 :) It helps to sleep over problems...

This morning when I woke up I knew where to find some plate that should work; amongst the scrap from the old dot matrix printers that I'm stripping for parts.  I found a bit that was 0.12mm thick - and appears to be stainless steel:


The third time round making a bit goes quick; a couple of minutes later, I had the valve plate spring:


All set up for silver brazing; I squashed a tiny bit of flux into the groove before fitting the two pieces together:


Poking at this lot with a thick silver brazing rod was hairy, but I got the job done - sort of.  After some cleanup:


Next I raided my acoustic guitar for its high E string - Its been years since I played it as I tend to hurt my ears - and started making springs; something I've never attempted:

I made a booboo on this one; I need a compression spring, not a tension spring; but it was good practice.  The spring's internal diameter must be just over 2mm in my case, so I used a 1.5mm drill bit chucked in reverse in the pin vise.  The start of the wire was just squeezed between the jaws of the pin vise with a sharp bend to get started, and I turned the chuck manually by left hand - while just keeping tension on the wire and guiding it with my right hand.

After making a compression spring, I had this:

Not the most beautiful - but functional.  It would have benefited from a proper guiding setup instead of just trying to wind the spacing by eye...

Next call of the day was the flywheel.  Roughly trimmed down to size on one side:

The boss in the center is called for in the plans; I nearly missed it - and would have had to make a spacer later on if it was not there.

When I built the Grasshopper engine, I made up this double-sided tool for doing undercuts in flywheels   :dremel: :


Flipped around, and the other side done.  For now, I left the excess on the outside, and only after I took this photo realized I had not completed the hub:


On to the RT on the mill; some 8mm holes drilled:


And then milled further with a 10mm end mill:


Back to the lathe, and this time with some suitable short stock chucked in the 3-jaw, then press the flywheel against the jaw faces with the revolving center - and with a bit of cardboard in between the wheel and jaws to provide friction.  Turning the rim to final size was then a breeze:


Then back to the mill to spot face, center drill, tap drill and thread the hub for a grubscrew:


I needed some M2 grub screws...  Some bits of M2 threaded stainless steel were slotted 0.5mm for a flat screwdriver:

I just used a junior hacksaw to saw them off after slotting while still held in the vise.

Hmmm, let's see now....  Going back through the plans, there's little check marks next to all the engine parts, and I made the additional ones I needed...  Al that's outstanding is the base and burner.  Some assembly followed, with some careful adjustments to work out a couple of tight spots, and a test with a recalcitrant pencil torch that does not want to stay lit with a smaller flame:

 :ddb: :ddb: :ddb: - it's alive; not very well yet, but a good sign   :D
I'll try and finish the base and burner tomorrow and get it running properly   :)

 :beer: Arnold

Offline scrapman

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Re: Arnold building the "Little Blazer"
« Reply #33 on: December 11, 2010, 02:26:56 PM »
Hi Arnold  :wave: interesting build and it's a runner :clap: :clap:,

Ray.

Offline Stilldrillin

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Re: Arnold building the "Little Blazer"
« Reply #34 on: December 11, 2010, 05:12:55 PM »
Arnold.
A runner!  :D You're wearing that big long distance smile!  :ddb: :ddb:

Very well done, and shown......  :clap: :clap: :thumbup:

David D

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Offline jamesemery728

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Re: Arnold building the "Little Blazer"
« Reply #35 on: December 11, 2010, 05:54:03 PM »
Very nice build Arnold and excellent pictures. I noticed in many of your mill pictures that it looks like you are using a small Dremel chuck to hold small drills. Can you tell me where you got the arbor that the chuck is mounted on. Did you make the arbor because I know that the small Dremel chuck has a very fine thread inside of it. Thanks and again what a great build.

Offline Dean W

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Re: Arnold building the "Little Blazer"
« Reply #36 on: December 11, 2010, 10:42:39 PM »
Arnold, I wasn't expecting to hear a running engine that soon.  It makes a great sound, and gets with it, too!
Your builds have been going very well these past months.  Well done.   :thumbup:
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Offline sbwhart

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Re: Arnold building the "Little Blazer"
« Reply #37 on: December 12, 2010, 03:38:33 AM »
Great work Arnold

 :clap: :clap: :clap: :clap: :clap: :clap: :clap:

It will be a real nice looking and running engine when you've got the base finished/

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline NickG

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Re: Arnold building the "Little Blazer"
« Reply #38 on: December 12, 2010, 03:42:25 AM »
Well done Arnold - another runner on Madmodder! It's fantastic!  :bow:
Location: County Durham (North East England)

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Re: Arnold building the "Little Blazer"
« Reply #39 on: December 12, 2010, 07:12:18 AM »
 Cracking Arnold  ,,,,,,, Cracking  :bow: :bow: :bow: :clap: :clap: :clap: :clap: :clap:




Rob  :)

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #40 on: December 12, 2010, 11:14:37 AM »
Thanks Ray!

Thank you David - the smile is even brighter today!

Thanks James; yes it's a Dremel chuck on a home-made arbor.  I'll dig up some photos and post it in the tools section in a bit, as it is a really handy piece of kit.

Thank you Dean; I think the powers that be is looking down kindly on my escapades; I'm really having a lot of fun in the shop of late!

Stew, thanks mate; I hope today's post meets expectations!

Thanks Nick - much appreciated!

 :beer: Rob; it's all your fault for giving me so much  :poke: :poke: in the past mate :lol:


Time to tidy up this one  :)

I started with the base, which I decided to make from wood for this engine.  A bit of Rhodesian Teak trimmed to rough size with the jigsaw:


Sacrilege! - but the flycutter works a treat in trimming down and cleaning up some wood :

I will really have to invest in some proper woodworking tools at some point!

I used a router bit to pretty up the edges of the block; the mill's top speed is a bit slow for routing bits, but it does get the job done:

Just needs some oil and a good rub-down with floor wax now...

On to a 3/4" to 1/2" copper pipe reducer; trimmed up and tidied up in the lathe:


A bit of scrap HRS turned down to a fairly tight push fit in the 3/4" section of the reducer:


The above was needed so that I could clamp the reducer at an angle in the mill vise without squashing it.  I only have 5.5mm diameter pipe for a spout, and no 5.5mm end mill, so I used a 4mm end mill to drill the hole for the spout, and then very carefully followed that with a 5.5mm drill bit.  A generous serving of cutting fluid was used; copper is one of the less fun metals to machine:


One of the projects I have on the back-burner is an experimental boiler build - and I learned one good lesson from that; It takes quite a bit more heat to re-melt silver brazing that was already done than to do new brazing.  With that in mind, I first silver brazed the spout in the reducer, then cleaned the bottom edge and bottom inside edge of the reducer very well with sandpaper, and made a ring from silver solder that fit in there:

Then I liberally coated around the silver solder ring with flux, being careful not to get any flux on the outside edge.  The foot plate is some 1.6mm brass that I just cleaned well with sandpaper.

I just carefully plonked the reducer part down in position on the foot plate, with a lump of steel on top to keep it in position, then let it sit like that for a couple of minutes so that the flux would gravitate down onto the brass foot plate as well, then used a blow torch to heat the lot up, concentrating the heat directly on the joint.  After a short while I could see some flux bubbling to the outside as it followed the flame, then it went black and then clear, and a second or so later I could see some silver brazing wicking through.  I used the flame right around the entire joint to draw the silver brazing through and let things cool down:

I'll happily admit that this is the best bit of silver brazing I've done to date   :dremel:

The tank was then dropped in some citric acid to have a bit of a pickle, and I started on the cap for the tank - a simple turning and knurling job:


Wicking was a bit of a problem; I'd used cotton based wicking on Fred the Loco's burner, but when the meths run out the wicking is inclined to smolder and burn off.  Amongst my junk prized collection, I have a sheet of fiberglass mat... Some judicious peeling away of fibers was done, and then all aligned and rolled into a kind of string; a bit fiddly, but I got it fed into the spout in the end:

(Now it had more hair than me  :coffee:)

I played barber a bit, and filled the tank with meths; A purple glow quickly appeared at the top of the wick, and I tested it:


Earlier while I was waiting for the meths tank to pickle, I'd also thoroughly oiled and lightly waxed the base, So I assembled the lot, and ended up with this:




A puff of graphite powder into the cylinder, a drop of oil on each of the running bits where needed; and a lot of fiddling with wick position; it's a choosy little bugger - but it runs  :ddb: :ddb: :ddb:

The second part of the video was taken in my study; in the shop it was 35C and in my study with air conditioning 26C - It seems to like running in the cooler environment a lot better!

A fun, but challenging little project!

Regards, Arnold

Offline Bogstandard

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Re: Arnold building the "Little Blazer"
« Reply #41 on: December 12, 2010, 11:39:21 AM »
Fantastic runner and build sequence Arnold.

I just can't believe how fast those ones run, mine just plods along at a few hundred RPM. Yours almost becomes airbourne.


John
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Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #42 on: December 12, 2010, 11:51:36 AM »
Hi Arnold,  You've got a fine runner there, it sounds and looks great.  I was going to ask the purpose of the solder, as the instructions in the magazine article made no mention of it, and my valve "spring" is a piece of copper about 15 thousandths thick, with a radius on its end fitting in the radius slot in the valve, and it holds fine although you can see the valve plate slide up and down a few thousandths when its running, and I was afraid it would cause a bind, when I saw you soldering the two together, but it obviously works well, and causes no binding or loss of vacuum.  You definitely proved out the superiority of iron, for the cylinder, and in keeping with the last video posted, I am going to machine an iron cylinder and replace my aluminum one with it, and put an iron piston in it as well.  I just finished boring out my latest ali cylinder about five thousands, turned a graphite piston for it, fitted it all together, and it runs, but barely so, and only for a minute or two, as well as being very finicky about where the flame is.  I found out a while back, once it is running up to speed and warmed up, it runs best with the flame as far away as possible, so it can get the hottest part, the top, sucked in, but too far will instantly stop it.  Kudos for a fine build, a fine log, and a fine looking and sounding engine.  I don't think I've seen anyone's build go as smooth and without hitches as yours has unless you kept all the frustrations bottled up inside, and didn't share them with the rest of us :poke:  Great Job, and I hope mine runs as well with a better set of bits and pieces. :bang: mad jack

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #43 on: December 12, 2010, 01:42:48 PM »
Thank you John - much more than just for your compliment.  I'd like to count myself very gratefully as one of the newbies who has learned a great deal from what you and other experienced machinists/builders have shared!

Thanks Mad Jack.  Yes, it is finicky about where the flame is; I had a look, and it runs best when it is sucking a nice blue bit of flame into the piston.  Setting the valve was fairly easy; I just tensioned the valve spring plate so that it barely holds the valve against the face, and also manipulated things that the valve is very flat against the face.  I didn't spend all that time flat-lapping for nothing ;)

Kind regards, Arnold

Offline Bogstandard

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Re: Arnold building the "Little Blazer"
« Reply #44 on: December 12, 2010, 03:32:18 PM »
Arnold,

Only a couple or three years ago, people were having all sorts of trouble getting these flame lickers running, and because of that, at that time, not many were ever built, and a lot of those that were, got thrown under the bench in frustration at getting them to run.

By everyone sharing their info about such things, it seems that anyone who builds one now can get the knowall to make a running engine.

Only by sharing, mistakes and all, does everyone become a winner.


John
If you don't try it, you will never know if you can do it.

Location - Crewe, Cheshire

Skype - bandit175

Offline Stilldrillin

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Re: Arnold building the "Little Blazer"
« Reply #45 on: December 12, 2010, 04:24:45 PM »
Arnold.
That's beautifully finished, and a superb runner. Well done!  :clap: :clap: :thumbup:

David D
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Offline Dean W

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Re: Arnold building the "Little Blazer"
« Reply #46 on: December 12, 2010, 06:49:27 PM »
Really runs great, Arnold.  I sure like the sound, too.  Very much like the sound of a small IC engine.
Well done, again!
Dean W.

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Offline scrapman

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Re: Arnold building the "Little Blazer"
« Reply #47 on: December 12, 2010, 07:37:16 PM »
Lovely runner and a nice build  :thumbup: :clap: :clap:,

Ray.

Offline NickG

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Re: Arnold building the "Little Blazer"
« Reply #48 on: December 13, 2010, 07:12:58 AM »
John is right,

Not an easy engine to get running because of their low specific power output, therefore there must be many under the bench or on the shelf having never run. People sharing ideas and problem solving on forums like this have undoubtedly helped a lot of people, I don't think I'd have got mine running without it. At Harrogate show somebody had built the same Jan Ridders (to a higher standard than mine I must add) but couldn't get a peep out of it. He was asking all sorts of questions so I took him through all of the findings that have been shared and we almost had it running at the show. With a couple of minor tweaks he would definitely have had a runner.

I haven't seen the 2nd (finished) video yet so something to look forward to tonight. I think the reason this, poppin and the like run much faster is because with a cam controlled valve you can play a lot more tunes with it.

Am looking forward to finish my poppin off, would be over the moon if it runs at all, let alone like yours arnold.

Nick
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Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #49 on: December 13, 2010, 10:41:21 AM »
Arnold,

Only a couple or three years ago, people were having all sorts of trouble getting these flame lickers running, and because of that, at that time, not many were ever built, and a lot of those that were, got thrown under the bench in frustration at getting them to run.

By everyone sharing their info about such things, it seems that anyone who builds one now can get the knowall to make a running engine.

Only by sharing, mistakes and all, does everyone become a winner.


John
  I think John is dead on target here, I built my "little blazer" almost twenty years ago, spent probably six months trying to figure out why it didn't run, and left it lying on different shelves as I moved.  It was only seeing someone else build one, look intensly through the build log, and seeing it running that made me pull mine out, find the errors I'd made, fix them, and finally have a good runner, good enough to be banned from running in the house.  It is particularly satifying to see someone like Arnold, start the project, follow a very nice build log and see success right off the bat, and recognise the amount we share with each other, particularly when we show our problem children, and get them running.  I can't speak for anyone else, but this forum makes me feel almost like I am in a club, and I really wish I could get together with the many fine artists I've watched build things of great interest to me. :beer: cheers to all, mad jack

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #50 on: December 13, 2010, 03:22:53 PM »
Thanks everyone  :beer: :beer:

Wood may not have been a good choice for the base.  It's gotten all stained with graphite powder, so when it starts to look really bad I'll make a new base for it from metal.

I had a lot of fun running it so far; took it to work for show and tell; it must have gotten at least 1 hour total run-time on it from that, as everybody heard the commotion and then wanted to see it run.  Even the MD popped in,sat down and watched it go for a full tank-full.  He seems to like the engines I build; after running it his comment was "Well, at least you didn't have to blow it like the others"  :lol:

At one point it got so hot that I actually burnt my finger on the flywheel when starting after a re-fill; soon after this it jammed up solid; with the piston wedged in the bore from heat expansion; once I let it cool down completely it was fine again.

And yes, I agree fully with John as well  :thumbup:, and have the highest regard for people who share their builds and their experience.   
A "Thank You" for that is sort of hollow; so I'm trying to return the favour by posting my own progress as I go along on my own personal machining journey.

Personally, posting up a build like this one on the Blazer is a bit of a hit-and-miss thing (even though it is a flame licker in this case ::)); I'm never sure if there's too little or too much detail, and it takes quite a bit of effort to post up as well - besides the time taken to type up things I have to be pretty careful while typing it up, as English is not my native language. And yes, I do attempt some bad puns on the side...
I try to tell a story while posting, with some "diversions" in between; these are usually just for my own benefit while thinking things through, but they end up as part of the posts.  The posts in this build log were all quite long - the result of simply getting more done in shop sessions than I used to in the past. 
A while ago I wondered whether it was worth the effort of posting in any kind of detail, and then I received a nice surprise over on HMEM; I received a PM from a complete stranger who had never posted (I really don't like to use the word "lurker") who, it turned out, had been quietly following along on quite a few of my projects. 
He was inspired by, and inquired about some of the "simple" bits 'n bobs I made "in between" on a build.  Receiving public acknowledgment for a build is very nice indeed and very much appreciated,  but that PM is what's made me decide to carry on posting in detail; just maybe someone else will be inspired by my little posts; just like I have been inspired by posts from others.  I'm open to criticism in my write-ups; if anybody thinks there is a way to make my posts more readable or usable, then please do pipe up or send me a PM.

Quote
I don't think I've seen anyone's build go as smooth and without hitches as yours has unless you kept all the frustrations bottled up inside, and didn't share them with the rest of us
Mad Jack - I forgot to respond to that; this build went exceptionally well - I shared all the frustrations and hitches along the way - even to the point of modifying a mill handle totally off-topic to stop a squeak,  sleeping over a troubling valve spring plate, and for the first time ever running my mill's collet chuck into the workpiece.  I've found that by building a model,  or any other workpiece,  over-and-over-and-over in my head before actually machining it helps a lot to prevent frustration.  I know my lathe fairly well by now, and can compensate for it's limits.  The mill is another matter, and I'm still pushing it gradually to get to its limits.  And I spare myself some headaches by just doing things the manual way; it can be really hard to try and figure out a way to clamp and position a workpiece to mill a curve and so on - a lot of the time it's quicker to just grab a file and do it manually!


Kind regards, Arnold

Offline sbwhart

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Re: Arnold building the "Little Blazer"
« Reply #51 on: December 14, 2010, 03:07:01 AM »
Well done Arnold a real fine engine that runs beautifully and a great write up to boot.

 :clap: :clap: :clap: :clap: :clap: :clap: :clap:

Thanks for sharing with us

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #52 on: December 14, 2010, 08:10:08 AM »
By the way, Arnold, I quickly discovered the staining of the walnut base I put mine on, and in keeping with the heat aspect you mention in your latest post, got inspired, took the head off a five horse dead briggs and stratton lawnmower engine, faced the head surface dead flat, flipped it, faced the surface of the fins flat, so they sit without rocking, and drilled the base of my engine to take two allen screws, and screwed it solid to the head, and when I had it with bronze piston and aluminum cylinder, it would spin up about like yours sounds, which checked with a digital tach was some 2500 rpm, and would run two "burners" of alki out before the piston would stick.  Unfortunately, unlike the cast iron, I had to "hone" out the cylinder with some 400 grit paper, and take off the burrs of the piston before I could run it again each time it stuck.  Added up to five cylinders and six pistons before graphite.
     I finally took a new generator brush, machined a piston out of it, got it all back together, and it barely runs, only runs for a minute or two while cold, and won't run more than ten of fifteen seconds when hot now, so I think I've got too much clearance with the non-expanding graphite piston.  Time to make an iron cylinder and go back to a bronze piston I think.  The cylinder head from the lawnmower engine is a fine heat sink though, and makes a big difference in running time when the rest is right.  I'm still kind of jazzed over the great running of your engine, really enjoy listening to it. mad jack

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #53 on: December 14, 2010, 10:27:20 AM »
Thanks Stew  :beer:  - I'm fighting with myself over what to build next  :lol:

Cheers Mad Jack; I'll leave mine as is for now.  A cast iron piston should do well too; in fact it might be better than bronze.  I'm just a bit stingy with my cast iron as it's horribly expensive and hard to obtain here in Windhoek; I usually end up wasting quite a bit of it because I can't get close sizes.  Bronze works out cheaper for me, as its fairly obtainable in closer matching stock sizes, so not as much ends up as chips for me.

Kind regards, Arnold

Offline cfellows

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Re: Arnold building the "Little Blazer"
« Reply #54 on: December 14, 2010, 11:12:58 AM »
Great job, Arnold.  Hope mine takes off as well as yours did!  One queston... I don't recall any mention in the oiginal built article about soldering the valve pieces together.  I thought the thin metal piece was held in the valve slit by spring pressure alone?

Chuck

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #55 on: December 14, 2010, 02:48:22 PM »
Thanks Chuck.   :beer:

I just went through Phil's build article again, and you're right! 

I don't know where I got the idea from it had to be soldered  :doh: - and that was the trickiest bit of the build for me - that was a bugger to silver braze  ::)
Setting the valve flat on the face would be a LOT easier if its not soldered - it would basically just be a simple job of adjusting the plate pressure - as long as the curve on the spring plate closely matches the slit on the valve plate and it fits fairly square in the slot - no need to faff around bending the spring plate to keep the valve flat to the face like I had to do!

 :lol: :lol: :lol: And I even wondered about what kind of "solder" to use for this part  :lol: :lol: :lol: - better go and edit the posts!

I hope to see your one running soon  :thumbup: ; making the engine base really took the most time and you're past that already.  Phil's instructions are excellent; the only bit I had a problem with was - and I quote:
"Finally, the last item in the valve push rod assembly to make (Photo 44) is the flat steel valve spring - no problem!"
 :doh: - That's all he mentioned about it and caused me the most grief!

Kind regards, Arnold

Offline cfellows

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Re: Arnold building the "Little Blazer"
« Reply #56 on: December 14, 2010, 09:42:00 PM »
All's well that ends well!  I haven't worked on mine for a while.  I've been bouncing around between projects.  Been doing some airgun work, building a new telescope, making some changes to my plumbing parts engine, and my opposed 4 cylinder air engine, which is now done. 

Chuck

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Re: Arnold building the "Little Blazer"
« Reply #57 on: December 15, 2010, 05:10:40 PM »
Hi Arnold, Iīm a bit late with my congrats, due to circumstances out of my control (a lightning bolt hit the house). An excellent build, and and excellent runner. Iīll just finish another Stirling, and then Iīll try my hands on a(nother) flame licker too. Your build will be closely watched over and over again, although Iīll probably make it somewhat different (donīt have the Duclos book). I very much like a build thread that goes into detail, why and how, as all of yours (and many othersī, Bogs gets a cookie/M&M...) do. Thereīs nothing like following behind a masterīs shoulder, when trying to learn how things work. Please, keep up the good work.
 :nrocks:
 :wave:
Olli
Penafiel
Portugal

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #58 on: December 16, 2010, 12:26:18 PM »
Chuck, I know the feeling of bouncing around...  I've found if I don't settle on a single project and get it done, I never get anything done.  Have a lot of stuff on the back-burner myself, and I'm going to start attacking them one-by-one... - though another more pressing project came up that I'll start and finish first.

Thanks very much Olli; much appreciated  :beer: I'm by no means a master of any sort; in fact I'm pretty much a raw beginner, so don't take what I do or show as the best way to do things.  In fact, I'm pretty much in awe of your work on Stirlings; that's something I'd really like to get my teeth into, so I'm learning from you as well.  I've found a supplier of laboratory equipment locally, and can finally get my hands on some test tubes, so it won't be too long now before I try one :-)

 :beer:, Arnold

Offline madjackghengis

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Re: Arnold building the "Little Blazer"
« Reply #59 on: December 17, 2010, 11:42:24 AM »
Hi Arnold, having watched your build from start to finish, I wanted to say first off, every detail you showed, everything you spoke about was taken in and well appreciated, much of it "old hat", but of good value even to one with experience.  In my own never too humble opinion, there was no excess, and those of a different opinion could skip over what was such in their minds.  I learn as much from people doing things for the first time, and starting from a different point of view, as I do generally, from the experts who show their mettle here, as we all bring different backgrounds to the forum.  Because of your build, I took a piece of salvage cast iron to turn a cylinder, and found it was too poor quality and porous to be used, but that induced me to use the other generator brush, after measuring my bore, and finding two thousandths clearance, and turning a new piston out of it, and taking great care to ease up to size, something I've got to learn patience on, as I'm accustomed to much larger parts and less need for the absolutes of accuracy, but now my engine will run until it is too hot, and will start again as soon as it is cool, where by leaving it alone for a while, or using my hands to cool it quickly, but I still need to fit a graphite valve as the bronze one is still scoring the side of the cylinder.
   Your first choice of cast iron for the cylinder never entered my mind, until I saw you take that turn, and that was a lesson for me, as I knew aluminum was a poor choice, yet used it anyway.  I am about to re-embark on the radial engine, now that I have most of the cleanup after the flood done, and the first inspection from the insurance company behind me, and I've got my cylinders back from honing, leaving me no excuses.
   Your build was very well documented, illustrated, and your immediate success was inspirational for all those who are beginners, you showed there is no good reason a beginner can't do an engine right the first time, it's just a matter of taking care, and taking the time to do it right.  All in all, I thoroughly enjoyed it, and got some inspiration of my own from it, even if it meant some of the other dozen or so projects got back burner for a bit.   :beer: here's to engines, and those who build them :bugeye: mad jack

Offline arnoldb

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Re: Arnold building the "Little Blazer"
« Reply #60 on: December 19, 2010, 01:43:41 AM »
Thanks Mad Jack.  Good to hear your engine is running better now as well  :thumbup:
As to your valve scoring the cylinder, that might indicate too much spring pressure...  I may have gotten lucky by brazing mine's valve plate to the spring; it means I can adjust it so that the valve is barely touching the port face, which helped a lot with friction reduction.

Kind regards, Arnold