Author Topic: "A Beginners Engine" From Model Engineer.  (Read 21090 times)

Offline ParCan

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"A Beginners Engine" From Model Engineer.
« on: July 28, 2013, 12:36:26 PM »
 :proj:

We after the first engine attempt last year (Puddleduck)  I have some workshop time again.

Model Engineer have just started a "Beginners Engine" series.
As with most things, I'm impatient and have started to get some of the bits underway (With minimal dimentions)

It requires a 4" flywheel. I put an inch thick round slab in my 3 Jaw and it was .2 mm or so out.
Out came the 4 jaw and the centre of one side is well under way to being hollowed out. (More Details in the Tools Thread)

Last week a couple of sheets of Perspex arrived. I decided they would be good to make the Base.
8 bits, 9 1/2"X 2 1/2" were cut and superglued together to make it 1" thick.
I have trimmed it down to the correct(ish) size on the mill.

This looks like it'll be a fun engine and maybe i'll stand a chance of getting it to work...

For every expert there is an equal and opposite expert....

Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #1 on: July 28, 2013, 02:35:47 PM »
:proj:

We after the first engine attempt last year (Puddleduck)  I have some workshop time again.

Model Engineer have just started a "Beginners Engine" series.
As with most things, I'm impatient and have started to get some of the bits underway (With minimal dimentions)

This looks like it'll be a fun engine and maybe i'll stand a chance of getting it to work...

I think I'm guilty for you getting  :proj:

You can find my build log her http://madmodder.net/index.php/topic,8438.0.html

Pleased you're having a go, hope you enjoy the build.

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

Location:- Crewe Cheshire

Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #2 on: July 28, 2013, 02:57:07 PM »
Hi there, i'll be watching as i am also building Stew's engine. It has stalled lately but hope to get back to
It tomorrow night.
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #3 on: July 28, 2013, 03:11:33 PM »
Stu: 100% guilty.

I'll have a read of your log over the coming days :)

Alex.
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Offline Stilldrillin

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Re: "A Beginners Engine" From Model Engineer.
« Reply #4 on: July 28, 2013, 03:43:15 PM »
I've seen Stew's original. It's much larger than I imagined, from his postings.  :scratch:

A nice engine!  :thumbup:

David D
David.

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

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

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #5 on: July 29, 2013, 03:16:15 PM »
I now have the Drawings from Stew. Thank you :)

I have been looking at the Cylinder and valve.

Forgive me, but where does the exhaust go ?
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Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #6 on: July 29, 2013, 03:22:11 PM »
ok - ok I see.
2 X 4mm holes shown 20mm apart under the valve chest.

 :doh:
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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #7 on: July 29, 2013, 05:44:12 PM »
I asked Stew the same question a couple of months ago! Don't know how I missed it.

 I do have another question for Stew though - how do you go about setting the valve timing when you cant see the valve and ports? Measure depth to back valve face through hole?
Location: County Durham (North East England)

Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #8 on: July 30, 2013, 01:20:51 AM »
I asked Stew the same question a couple of months ago! Don't know how I missed it.

 I do have another question for Stew though - how do you go about setting the valve timing when you cant see the valve and ports? Measure depth to back valve face through hole?

I did it by looking through the single inlet port, when the crank at the 12:00 oclock position you adjust the eccentric so the valve is not quite covering half the hole. second drawing from the top of the valve events on attached drawing shows this.

Hope this helps

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

Location:- Crewe Cheshire

Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #9 on: July 30, 2013, 01:10:00 PM »
Thanks Stew, way off yet but good to know.
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #10 on: July 31, 2013, 02:36:05 PM »
Ok: Both sides of the Flywheel are made.
Centre is reamed to 8mm and fits like a glove on my Stainless steel shafts.

Just need to chuck it up again to skim the outside edge.
I do however have concerns gripping a 9mm deep shoulder / 20 mm dia (I still have a mm to remove if need be) and turning the edge off something 100mm dia.

Are my concerns unfounded ?

Suggestions welcome as always.

Then it's off to the Mill and rotary Table to make nice holes in it.
Never used the table (Bootfair find) It's the same size as the fly wheel (100mm) so clamping clues welcome.
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Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #11 on: July 31, 2013, 05:20:32 PM »
I do however have concerns gripping a 9mm deep shoulder / 20 mm dia (I still have a mm to remove if need be) and turning the edge off something 100mm dia.


That's how I do it, should be fine, just don't run the lathe fast or it will chase you round the shed if it comes off  :D and take small cuts.

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

Location:- Crewe Cheshire

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #12 on: August 05, 2013, 04:09:01 AM »
Hi Guys.

Flywheel is now complete.
It's on centre, and looks like it's going to be ok.

Started on the Cylinder yesterday, I'm making it from Cast Iron (Sash Weight) cos I have some of a suitable size.

You know it's getting hot (Drilling it to 12mm) when your squirt of coolant boils as it touches the work !

I'll complete the bore today.

My Boring tool is rather small but it seems to cut the Iron nicely.

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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #13 on: August 05, 2013, 05:42:02 AM »
Cast iron will be good, i am using cast gunmetal for mine as have a bit the right size. Is your drill blunt or were you running it too fast? Slow cutting speed for cast iron and it doesn't usually get hot in my experience.
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #14 on: August 05, 2013, 06:08:39 AM »
Hi.
Apologies for the Picture size in my last post....

The drill was brand new when I started. It's now somewhat 'used'
Cutting speeds were slow (slowest on an ML7 without the back gear) and I believe appropriate.

Cylinder is bored to 16mm (tight fit on a 16mm Milling tool shank)
Made a Hone out of some Plastic, Probably Nylon, 50mm long X 16mm dia to make it a sliding fit. Tapped one end blind M8.
Starting with Course grinding paste, then fine, I ran the bore up an down the hone for around 10 mins.
Clean down with White Spirit between each paste.

A Quick final with Solvo Autosol (Very Fine) I now have a smooth bore with a fine crisscross of light scratches.

Now it's time for a thorough clean down of the lathe. (to get rid of both the Cast Iron and the Grinding paste)

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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #15 on: August 05, 2013, 07:42:47 AM »
Looks good.
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #16 on: August 05, 2013, 09:01:36 AM »
I now have a flywheel with 6 decorative holes in it.

Rotary Table is, er , well - um: not good
Put a Centre into the Mill (had to take the Draw Bar out)
Centred the table and bolted it down.
Checked the runout on the edge - looks good to me.....
Dropped the same centre into the flywheel.
Bolted the flywheel through the centre hole, Checked the runout - 3rd time I got lucky !

Then you encounter the lash. About 1/4 turn of the handle each way.

Centre drilled 6 places (60 deg apart), then 5mm and 13mm drill. (The largest I have)
That all went well.

The only thing I have 16mm is an end mill. That would have to make said 16mm holes.
The lash coupled with a VERY poor clamp screw has confirmed which side is the outside !

Anyway, 6 X 16mm holes in the flywheel sorta 60 deg apart....
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Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #17 on: August 05, 2013, 10:42:48 AM »
Fly wheel and cylinder looks good  :thumbup:

I drilled with four 22mm holes but it made my old drill sweat a bit, so drew it up with 6*16mm ish holes near enough is good enough for position I just marked mine out and went for it  :D

I know of three engines being made out there  :whip:

Stew

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

Location:- Crewe Cheshire

Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #18 on: August 05, 2013, 12:36:15 PM »
Yeah nobody will be able to tell. I always mess them up the lightening holes!
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #19 on: August 05, 2013, 12:48:52 PM »
Hi Stew

You have probably gathered that I'm not an experienced Engineer !
Finding Documented projects out there is always hard. The ME Article got me interested in this one, then your write up on here gave me the missing bits I need to get going.

The Puddleduck I built was in reality beyond my ability. It was and was supposed to be a challenge. I knew that the chances of it working were slim.
Saying that, John's Docs were easy to follow and gave me enough info to really learn how to do this stuff.

Your Engine looks like I can both build it and it will work at the end of it all.

Looking at your Youtube Ch I'm in awe of the stuff you have built. I looked at the Dake Engine but decided that would be beyond my ability. The Simpson engine is a work of art.
 
Oh - and where do I get a Wobbler Bar (used to center the Piston Valve ). Does it have another name ?
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Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #20 on: August 05, 2013, 01:57:33 PM »

Oh - and where do I get a Wobbler Bar (used to center the Piston Valve ). Does it have another name ?

Hi Alex

I'm not sure if it has another name I think its one of those things that people sort of call it different things I've just always known it as a wobble bar.

Where you get them from:-

You can make one all you need is a length of 10mm ish diameter silver steel clock it up in the lathe so that its running as true as you can get it, you may get away with the three jaw if its a good un, if not use the independent four jaw, then put a female centre in the end with a centre drill, swap it round and clock the other end true then slew the compound over 30 deg and turn a cone on the end, you can use it as it is or you can harden the pointed end by heating it up to cherry and quenching.

Or:- you can use a solid morse taperd centre, check that it has a female centre in the end.

Her's a picture.



Hope this helps

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

Location:- Crewe Cheshire

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #21 on: August 06, 2013, 09:07:36 AM »
More progress today.

Valve and Piston made. Body was easy enough, piston not so. Got it on the 3rd attempt.

Then I decided it was time for Small holes in Cast Iron time.
Centre punch did sweet nothing so I used a centre drill in the mill to mark each hole before drilling.
Drilled the Ports and used a small milling cutter for the Bore cutout.
Drilled the holes for the Valve. They both wondered a little so opened em out to 4mm.
The 8 X 1.6 mm holes were not fun, neither was the Tapping of said holes.
Just to note, I didn't have a suitable clamp, I Super Glued the Body to the Cylinder then spotted through with 2 mm and drilled 1.6 before removing the valve body and tapping the holes.
I'll leave you to guess where the rest of that tap is !

Piston rod is also done. I may do the piston later.

« Last Edit: August 06, 2013, 12:09:29 PM by ParCan »
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Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #22 on: August 06, 2013, 01:32:49 PM »
And more progress.

Brass Piston is made and attached to the piston rod. I turned the last bit with the piston mounted on the rod.
Lump of 35mm dia Brass arrived today so made the end caps. Still need to drill them for the mounting holes.
Piston almost runs freely in the bore. I'll knock a tiny bit off the locating 16mm dia.

I'm trying to work out the lesser of the evils for fixing the end caps.
I either drill 3mm all the way through the Cast Iron and mount the caps with studs.
OR I can drill and Tap M3 as per the drawings.
This lump of iron is darn hard in places.....  Comments and ideas welcome.
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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #23 on: August 07, 2013, 11:39:08 AM »
Alex, good progress there. Would be bit unorthodox drilling right through the cylinder but can see your point if you had a long enough drill and 3mm studding - Could get away with drilling only 4 holes rather than 8 and tapping 8 threads. Or if you could do with both covers clamped in place that's another 8 holes you don't have to drill!
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #24 on: August 07, 2013, 11:52:10 AM »
After another day in the workshop, the assembled list now includes.

1 X Cylinder : Complete
2 X Cylinder end caps : Complete
1 X Piston Valve : Complete
4 X crosshead rails : Complete
I need to do cleaning and filing bits to make thing look nice.
A blow in the requisite hole moved the piston appropriately.

I decided to Drill & Tap the cylinder holes as per the standard method.
8 holes tapped with no breakage though some are rather shallow. I can't get 10mm long screws in at the moment.
I have nice screws for the final build but it's all gone together.

I Super Glued the End caps to the Cylinder and used the Mill to position the holes.
(8.5mm each way from centre seemed to be close enough to work)
I then centre drilled the end cap, Drilled 2.5mm for M3 then knocked the end cap off.
Turn it over and repeat for the other side.
I then drilled the end caps 1/8 " (3.2 mm) on the pillar drill.

I'm rather pleased with the outcome so far.

(edit) Um - I have just seen a problem in the photo's.
1 Brownie point to anyone else who can spot the mistake......

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Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #25 on: August 07, 2013, 12:01:22 PM »
Looking good Alex.

NickG is building his from the other end and he came across a couple of mistakes on the drawings so her they are:-

Part MP39 crank shaft spacer the hole is 6mm diameter

Part MP30 crank shaft better to make it 100mm long

Part MP33 Main Bearing it should be 10mm wide

I've added V2 of the drawings
 
Cheers

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

Location:- Crewe Cheshire

Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #26 on: August 07, 2013, 12:03:29 PM »
Looks great. I may use the same method fir the cyl / caps unless i get my rotary table up and running and am feeling confident!
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #27 on: August 07, 2013, 12:24:27 PM »
Hi Nick
I have a rotary table but no method of fixing a chuck to it.
My Table is also rather cheap n nasty with heaps of lash in it.

I centred the Cylinder with the end cap glued in place.
Chuck up a bit of 4mm rod (that fits in the gland hole) Use that to centre it.
There is a vertical V in my vice. Used that to locate the cylinder in the vice for when I turned it over. 
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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #28 on: August 07, 2013, 02:08:23 PM »
Mine is a 6" vertex and feels great with little backlash but never used it, the clamps look good too, 1 either side of the table. I had no way of putting chuck on it either but have just bought an ML7 so have ordered a 2mt to myford thread adaptor which would let me leave the bits in the chuck and transfer to the table. Should be an interesting experience if nothing else!

Ah good idea, i've tried something similar in the past but don't have the luxury of the vee in the vice.

I also bought stevensons er32 collet blocks sq and hex for this sort of thing but then realised my collet set is er25 - doh!
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #29 on: August 08, 2013, 11:58:38 AM »
Hi again.

Another productive day.
Crankshaft, Con Rod and Crosshead completed.

I Started 3 Crank Webs just in case. All 3 came out pretty much perfic.
Crankshaft was all rather loose so I decided to Pin it. Broke a drill in 1 web so that became the spare by default.
I decided to use screws as the pins. Easy to get out. Final will have Grub Screws in it I hope.

The Con Rod I decided to make as 1 bit.
I didn't have any steel the correct width which would make attaching the Big End bearing a bit of a nightmare.
I also don't have any 1/4 square Brass. (I plan to mill the cross head slides from what I have)

I did the crosshead on the Mill. It's a tiny bit shorter than the drawing.
Also note. The M3 Thread for the Piston Rod should be M4.

Big and Small end bearings are Oilite Bushings I had in stock.

 
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Offline DavidA

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Re: "A Beginners Engine" From Model Engineer.
« Reply #30 on: August 08, 2013, 04:53:31 PM »
ParCan,

It's a bit late now, but I missed the thread.

Sash weights are often chilled.  I once bought a sash weight for a job and had to give up on it as it was too hard.

Sorry for not noticing earlier.

Dave.

Offline krv3000

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Re: "A Beginners Engine" From Model Engineer.
« Reply #31 on: August 08, 2013, 05:37:32 PM »
Looking good Alex.


Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #32 on: August 09, 2013, 06:30:05 AM »
Eccentrics today have not gone well.

I decided to make a steel inner and Brass strap.
The only suitable steel I had started out at 2" dia. A few passes of a roughing tool sorted that ...

I turned the 20 mm X6 deep shoulder.
Out came the Parting tool which really struggled in the std tool post.
Decided to try the rear parting post for the first time and I have to say it worked a treat on the 1st bit.

And I parted it off all the way.

Moved 1 jaw of the 4 jaw 3.5 mm measured with a drill.
Pushed the work across, Double checked the 3.5 mm offset and centre drilled it.
Then I looked at the first part which was missing said 8mm hole  :doh:

Turned the 2nd bit and then tried to part that off.
Tool post was hitting the chuck so took that off.
Then the jaws were hitting the Saddle (by quite a margin.)
Had to move the tool post as far as I dare off the side off the cross slide.

Carried on and hacked my way around the missing hole issue....
I superglued the 2 bits together back to back. Centred them on the mill. Centre drilled the 2nd part, then reamed them both to 8mm.

As I have some tiny M2.5 grub screws I decided to grub screw both bits.
The Eccentric strap was a simple turning and boring job and has come out really nicely.

 

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Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #33 on: August 09, 2013, 07:19:23 AM »
When parting off Alex don't be afraid to resort to the Mk1 parting tool:--- the good old hacksaw:- we all resort to it if we were honest  :headbang:

Looking good I recon at this rate we will be seeing a video of the running engine soon  :whip:

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

Location:- Crewe Cheshire

Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #34 on: August 09, 2013, 10:01:55 AM »
Yeah good progress there alex, the con rod and eccentric look good.
I had trouble with the crank too i may have to re-make. The trouble was i had to turn down to 8mm and the 8mm end mill gave me a good fit on the bearings didnt on the webs for some reason! Had i realised i had a 5/16" reamer i would have made it that size instead. i might use grub screws rather than pins if i make another But if i can get away with fixing the existing one i will do that as it took ages!
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #35 on: August 09, 2013, 11:16:13 AM »
Did all the tiny bits after lunch.
There is something strangely sadistic about making 1/4" square steel blocks and putting a hole in em !
All the Piston valve connection bits made.
Crosshead slides made.
Valve rod guide made.

The Boss will probably stop work over the weekend.

I now have the 4 Pillars to make, the 2  Bearing stands and the Base. I think that's about it.

The whole thing feels free as it stands. We will see what happens when I start to bolt it down.   
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Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #36 on: August 09, 2013, 11:24:47 AM »
I had trouble with the crank too i may have to re-make. The trouble was i had to turn down to 8mm and the 8mm end mill gave me a good fit on the bearings didnt on the webs for some reason!

I have 8mm Stainless rod and an 8mm reamer. Also 6 mm Silver Steel crank pin and a 6mm reamer.
Why they came out so loose I have no idea.
What I have here and now Is imperfect as far as I'm concerned, but it should work.
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Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #37 on: August 09, 2013, 12:41:05 PM »
I had trouble with the crank too i may have to re-make. The trouble was i had to turn down to 8mm and the 8mm end mill gave me a good fit on the bearings didnt on the webs for some reason!

I have 8mm Stainless rod and an 8mm reamer. Also 6 mm Silver Steel crank pin and a 6mm reamer.
Why they came out so loose I have no idea.
What I have here and now Is imperfect as far as I'm concerned, but it should work.

Are you using machine reamers or hand reamers: Machine remers are parallel along their length Hand reamers are tapered at the start and usually have a square on the end for a tap wrench.

If you put them through under power held in the tail stop in a chuck the chances are they cut over size due to misalignment best to drill out under size to within say .3mm ish then put the reamer through by had so that it cuts true, if using a machine reamer they are best put through with a floating holder or push it through on a carrier with a running centre, like this.



that way it will cut true size.

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

Location:- Crewe Cheshire

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #38 on: August 09, 2013, 01:34:07 PM »
I have seen this done before and used this method for the Valve Body which I did on the lathe..

I did the crank webs on the mill.
8mm ER 25 Colette.
Used an 8mm dia Centre drill to locate.
Then through with a 7.5mm a few times.
Then through at around 100 rpm with the Machine reamer.

Same process but 6mm all round for the other end.

I thought I'd at least get them to be a tight fit...
Reality is they are a sliding fit at best.
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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #39 on: August 09, 2013, 02:39:08 PM »
They should be a nice sliding fit when reamed which is about ideal for loctite. My 1/4" crankpin was like that.
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #40 on: August 10, 2013, 09:11:53 AM »

BOTHER BOTHER BOTHER ( or something similar)

The M3 Holes for the cylinder caps were rather to shallow. I went back through with a 1st and 2nd tap as far as I dare.
The 3rd tap was getting tight so backed it out. Was about a mm to shallow still.

I guess you know where this is going......

I got to where I stopped last time, 1/4 on 1/2 back. 1/4 on 1/2 back 1/4 on 1/4 back and that was it.
After a good careful wiggle On and off the tap was trapped.
More fluid but alas it was stuck on the back cut.

Anyway made the Crosshead posts this am.
They are currently all over length at the moment.
I can take the tops off on the mill to make em all the same height.
Whats the best way to do these on the lathe ?

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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #41 on: August 10, 2013, 10:03:18 AM »
I just measured how much needed taking off each one with a mic and then took a final facing cut in lathe.
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #42 on: August 11, 2013, 01:18:42 PM »
Managed to get a bit of workshop time over the weekend.

Crankshaft Bearing holders are done. Not happy with these so will probably re make.
Crankshaft bearings are done.
Pillars are complete and all the same height. Broke yet another Tap. I'm really not doing well with these small threads and it's always on the Back cut.
The 16mm Steel Bar I had was a freebie and does not cut or machine well. It's not even round by about a mm. Really cheap n nasty no doubt.

If there is 1 lesson I have learned from this project is cheap nasty metals do not help you. They are not nice to machine, Don't give you a nice cut, the finish is poor and it's not consistent to machine.
The Sash Weights are Glass hard in places, Machines wonderfully in other areas. Drilling the ports the drill would go in clean and nicely for a few mm then start to snag and snatch, I'd get through the hard bit and it'd drill fine again.

I still have not got the tap out of the Cylinder. Going to try and heat it tomorrow. It'll be double or quits.

temporary Base is made from 1/8" Perspex and drilled. I plan to use this as a template for the real base.

I have started the initial assembly. Can't complete without M2 nuts, I really do hope these turn up on Monday.
With luck I will be making a video on Tuesday...
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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #43 on: August 12, 2013, 05:37:54 AM »
Alex, I learnt that a while back and started buying in what metal I needed - it is much easier to machine, get better results and can save any heartache! I've not got bits left over that I want to use up but have found myself wasting time brining stuff down to size as I've said. Next project I will buy what I need for the price of it, I am quite spoilt by having M-Machine metals only 7 or 8 miles away though.

Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #44 on: August 12, 2013, 10:47:30 AM »
Despite heating the Cylinder and really carefully trying to get the tap out, it's broken inside.

Oh well. win some and lose some....

With the Inlet / Exhaust on the wrong sides of the valve and 2 broken taps in the cylinder I may well remake them.

The rest is now together and runs fairly smoothly.
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Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #45 on: August 12, 2013, 11:12:47 AM »
If you have all the bits made my as well give it a try just for fun before you remake.
As youre breaking taps try using a slightly larger  tapping drill you will still get a good thread
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #46 on: August 12, 2013, 02:19:04 PM »
 I always go 1/2 turn forward 1/2 back too and usually withdraw completely at least once to clear swarf. Still get the odd breakage though. Are they broken on cover bolts or for the valve chest? Could turn cover a bit and re-drill if it's there.
Location: County Durham (North East England)

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #47 on: August 12, 2013, 03:46:57 PM »
Hi Nick

I have an M2 in the Valve Chest. That was my fault and totally accept that. Simply to ham fisted on the Back turn.

I have an M3 in the Cover End cover.
This one I don't get. I was gentle and using a Jig to hold everything square.
I had Cutting Fluid and knowing that this iron is not the best thing to thread was using fair force and taking things slowly.
The tap had been in and out probably twice to clear dust and swarf.

Anyway - everything is together here and now. The 4 Crosshead pillars are slightly to tall causing the Piston rod to bind. That's easy enough to sort.
The eccentric was fun to get setup but the throw is now correct. Just need to sort the timing. 

As the drawing was not quite correct I have to sort out how I mount the flywheel. I'll prolly put a pin through the Shaft.
Plan B would be to Knurl the shaft and some Stud lock maybe.

That should all be doable tomorrow am, then I'll see if it's a runner.
 
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Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #48 on: August 13, 2013, 08:43:24 AM »
After a fun week in the workshop I have a completed engine.

Gasket gunk applied to the end caps and valve.
Oil in the air pipe

Time to see if it runs I suppose....


and



I'm rather pleased with the results....


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Offline NickG

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Re: "A Beginners Engine" From Model Engineer.
« Reply #49 on: August 13, 2013, 08:46:43 AM »
Great result! Well done  :clap:  :bow:  :beer:
Location: County Durham (North East England)

Offline vtsteam

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Re: "A Beginners Engine" From Model Engineer.
« Reply #50 on: August 13, 2013, 09:17:33 AM »
Excellent! Congratulations! Persistence pays off  :thumbup: :clap: :clap: :clap:
 :beer:
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline sbwhart

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Re: "A Beginners Engine" From Model Engineer.
« Reply #51 on: August 13, 2013, 10:48:48 AM »
Well done Alex a great job well done, I bet you're well pleased :-

It runs real well

 :D :D :D :D :D :D :D

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

I hope you enjoyed the project.

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

Location:- Crewe Cheshire

Offline Stilldrillin

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Re: "A Beginners Engine" From Model Engineer.
« Reply #52 on: August 13, 2013, 12:25:37 PM »
That's great to see!  :thumbup:

A first time runner. Well done!  :clap: :clap:

David D
David.

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

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

Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #53 on: August 15, 2013, 12:44:12 PM »
Flushed with the success of the engine, I have been screwmangling.

I decided it's time to make a chuck holder for the rotary table. Also need to make a spindle for my Dividing head (from workshops books).
This is my first go at screw cutting, In came the Back gear and took it about as slow as the ML7 will go.

Then I started to Browse Ebay, which almost always lands me both in a great deal of trouble and costs me money.....
http://www.ebay.co.uk/itm/Myford-Super7-lathe-/300947767330
looks rather nice n tidy, yes it's a seller refurb but it's been reground and looks to be nicely finished....

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Offline ParCan

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Re: "A Beginners Engine" From Model Engineer.
« Reply #54 on: August 16, 2013, 06:37:29 AM »
Made the Spindle and the Chuck adapter yesterday.
That's all glued up with thread lock.

Made the base clamp today, again all between centres.

Final product looks good to me :)

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