Tina :- Engine and Boiler Build

[klank]

I hope to post this build as it proceeds, warts and all over quite a few weeks - maybe of interest to some of you thinking of a new project or getting involved with steam for the first time?
I am by no means an experienced model engineer so please be kind if my attempts look a bit ragged compared to so many truly excellent finished works you always see on here.
The text may be a bit basic and simple, but I would hope doing this on  a "how to" basis might be of use to newbies and tyros alike.
 
This is a straightforward horizontal steam "mill engine" kit "suitable for a beginner"!!, together with a vertical fire tube boiler of sufficient capacity to steam it or other similar sized engines.
The engine includes an eccentric driven feed water pump.
The kit(s) have been around for quite a long time, but I have not seen them posted as a build before.

Background
For the last 6 months or more, I have been struggling to build a model "wall" engine - the kitted version of "Rachel" (a German original design) and distributed by GLR. I obtained the castings from Dave Clark (editor of ME) - who had decided not to proceed with it.
Rachel is a B***H - good looking but very fiddly and difficult to understand. (Strangely, it is no longer currently listed as a kit by GLR!!)
It has turned out to be an engine from hell - and I was getting so frustrated with it, that I felt a change of project was in order and to put this nightmare on the back burner for a while..

My dear wife gave me the green light to look for another long term project, so after due consideration, I decided on a more straightforward horizontal steam engine.
I liked the look of the Stuart Victoria, but for nearly the same price, GLR (I had better say here - usual disclaimer) offer both an engine AND kit of boiler parts/plans to make a vertical fire tube boiler all at a usefully discounted price. It is often advertised in the ME magazine, and was the subject of a lengthy build series (both engine and boiler) in the ME by Stan Bray back in 1996/7.

I placed the order with GLR by telephone, and was delighted to receive a telephone call from them the following day to say that the kit was being boxed up and would be sent by carrier that night - "Would I be in to sign for it on the following day?" - very good service.
There was a minor issue in that the boiler funnel tube and two small castings for the top slide bars were not included but would follow shortly. How very refreshing to get an honest deal!!

Sure enough, a large heavy box was delivered the following morning - this is what was inside :-






Note - I posed this picture after I had done some prelim. work on the bed casting - hence it is painted black (by me) and not in its original - as cast condition.





All of the castings for both the engine and boiler smoke box top are in gun metal and look to be excellent - very little flash/imperfections or unwanted "bits" sticking to them.
The engine bed plate is a substantial aluminium casting - virtually useable "as is".
There is also a handsome mahogany sub-base, ready with appropriate slots for the flywheel and crank disc milled out. This is an "extra", not included as standard - to indulge myself.
The engine has a bore/stroke of 1" by 1.5" and flywheel of 6" dia.
The boiler is approx 8" by 4" dia. (including smokebox and firebox spaces) with 25 fire tubes.
All extra materials, fixings and plans (including two bound handbooks of Stan Bray's engine and boiler build articles) are also included.
Boiler fittings are not included - although sufficient phos. bronze is supplied to make all of the boiler bushes and hex brass for steam/water valves etc.
I will have to turn up boiler flangeing plates from some suitable material. Copper sheet of the correct thickness for the flanges is provided.
The boiler design is based on that published in the ME back in the 1950's - including a weight balanced safety valve!
The boiler may be fired by propane gas or coal (fire bars for the grate are not included although stainless steel and copper for the firehole door and ring are provided).

So, to begin.

There is no particular order to follow in making the engine, but it seems logical to start with the bed.

As I said earlier, the bed casting as supplied appeared very very good - true on both sides after a quick check with a rule held across the faces whilst held up to the light, and no obvious signs of twisting. Virtually no flash or imperfections anywhere.
The supplied plans give dimensions for the drilling points on the various "pads", and the height of the pads above the bed proper, but no basic data as to their positioning nor the overall dimensions of the bed. One must assume that the casting is accurate on that score.

To properly check for accuracy, I used "engineer's blue" spread thinly on a granite surface plate.
Now that sounds very professional - but to disabuse those of you with an eagle eye - my granite surface plate came from Tesco (a food supermarket) - in their "kitchenware" department - sold as a "Trivet/Worktop Protector". Supposedly made from solid granite, ground and polished. Its 14" by 18", 1/2" thick. All for less than a tenner in cost - this seems a bargain! A large ceramic bathroom tile would do just as well.

Engineer's blue is amazing stuff. If you leave the lid off the tin overnight, the gooey blue jelly will be found up the wall and creeping onto the ceiling, never mind on your clothing and lounge furniture. Do take care - a little goes a long way, trust me on this.
The base was shown to be pretty good, but some of the top face pads would need attention - they were all above the required height above the main top surface.

Anyway, I gave the base of the casting a lick over with a two point tipped tool (in place of a flycutter). Very little needed taking off. The "wedge" block clamps I made earlier proved their worth in setting up on the table - dead simple and easy.







I now had a true surface to place on the milling table/wooden packing beneath and could deal with bringing the pads to the correct height and milling out the flywheel/crank disc slots more neatly.
The back edge of the base was a bit out of true, but the other edges were good to go.







Points to remember - using a "tipped" cutter - the aluminium material tends to "weld" itself to the cutting tips as the work proceeds - needs frequent cleaning off to maintain a good finish. You can see a few imperfections due to this. I suspect the same problem will occur with a flycutter?

I then gave the bed a quick spray over of black engine enamel (from an aerosol) ready for marking out the pads for drilling/tapping the mounting holes.
I mounted the bed on a pair of accurate angle blocks with engineer's clamps and set - to with my vernier height gauge so as to get all of the drilling positions as accurate as possible - I could have done it by coordinates on the mill table - but from some little experience, for me this is a recipe for disaster, what with backlash and no DRO's.
I wish I had a DRO height gauge - easy for re-setting to zero. With a vernier one, you must concentrate on what you are doing and "where you are" as you move up and down. A cheapo calculator is of great help.
Note - suitable background music may help here - I am getting very deaf now, so I have equalised all of the music to + 87db. on my mp3 player - played back via an old audio amp/speakers in the workshop. Who am I to deny the delightful sounds of Bob Marley and classic Stones to my neighbours and my household?





Before this, I had spent some time changing all of the given plan dimensions from imperial fractions (as supplied) to metric. Just my choice.
I also photocopied all of the many plan pages so as to keep the originals as pristine, and the copies for annotations/changes and comments plus oily finger prints on the bench.

More to follow.

   

[sbwhart]

Hi Peter

Looks an interesting engine, and you've made a good start, look forward to following your build log.

Stew

[DeereGuy]

Peter,
Nice to see you are going to have a build thread.  Looks like a nice kit to build and it's good to hear things are in good shape with it.

I see you have marked directions of which way to crank the Z for up and down...  Is your sense of direction going as well as your hearing???  J/K I had to do the same thing with my feed directions on the lathe..

[Rob.Wilson]

Hi Peter


Thats looks a very good kit of materials you got yourself there    ,, and can see this will be a good thread to follow 

I have also noticed you have put your wedge clamps straight to use on holding the base casting 


Rob

[saw]

This was an intressting project, I will be follow you. 

[klank]

Thank you all for the very kind encouragement guys. I hope this will still be a worthwhile thread in a few week's time.

Stew - I am in awe of your Southworth and the watchmaker skills you and others post with such gay abandon (!! well you know what I mean) - this basic beginners' kit would be a piece of shlock/ easy peasy for all you guys - knocked off in half the time no doubt.

Bob - yup, I am getting deaf as a post but it is not (yet) affecting my sense of direction. Honestly - I use a Botch Li-Fe batteried drill/screwdriver with a simple adaptor in its chuck to push onto the Z axis drive shaft, with a keyway cut out, in place of the handwheel. Acts as a poor man's power drive up and down (that milling head is d**n heavy). I still cannot remember which way the direction control switch should be for "right and left" on the drill - so I give it a quick pull on the trigger each time and match the chuck movement it to the arrows on the base of the mill. Stupid, I know - but very effective - leaves little chance (ha ha) for getting it wrong - mind you, that's not to say I haven't had the odd coming together under power if you know what I mean?.

Best wishes/respects to everyone

Peter

[lordedmond]

Have GLR corrected their drawings for the boiler?

they supply stays but they are not on the drawings ( as supplied to me ) nor is the SWP ?

I have the boiler kit under the bench so to speak , when the current big job is done about 4 years in with another 4 to go ( BR class 4 tank in 5 inch gauge )


Stuart

[klank]

Stuart,

You've got me worried a bit now.
The boiler plan, as supplied shows no sign of stays - neither do the various abridged plans, nor text in the boiler build handbook - re-publishing Stan Bray's build articles in the ME.
The full plan appears to be that which was published in the 1950's - going on its style/layout.
Absolutely no mention anywhere of stays - and no Phos. Bronze rodding supplied for this in the materials pack.

I (possibly wrongly) assumed that the boiler was rigid enough by virtue of the fire tubes and gauge of materials and by the lack of reference to stays in the literature. - am I in error here?
If so, I will get back to GLR.

Showing my ignorance - you mention "SWP" - what is this?

Regards

Peter

[lordedmond]

SWP   Safe Working Pressure

It looks like you got the same reprint plans as I have it does not show stays but they supplied them , when the boiler first came out they advertised it as 80 psi then later they advertised it as a 40 psi unit


DAG Brown has modified one with more tube and fire box stays ( 1/8 copper rivets silver soldered in round the fire box area two row 1 inch centres i believe )

its the stress on the fire box inner that the trouble its very close to the yield point after you have made the boiler i.e. fully soft .

So mine will be stayed

As a note I did make all my boilers ( loco ) but they are to heavy now I need wheels myself ) the one for the current build cost 2.3K Squids

you will not need stays vertically as the tubes will do the job just fine its the fire box inner thats the trouble , its better to over build with stays now than which you had


If you look up the 3 1/2 boiler build by swhart you will find a good guide

http://madmodder.net/index.php?topic=2998.0


Stuart

[klank]

Thank you Stuart.

SWP - d'oh - sorry to be so stupid.

The build handbook for the boiler by Stan Bray, mentions :- "Suggest the safety valve adjusted to 40p.s.i. and see how it goes (???!!!). (Quote):- "The nominal working pressure for this boiler is 80psi but its initial test should be to 160psi."
Well that's helpful isn't it!!
In view of those sort of pressures, I would have thought that stays are a MUST - you are absolutely right!.
I shall contact GLR tomorrow about this.

Thanks kindly for the link.

I used to watch the class 4's in and out of Waterloo on empty stock etc. A very handsome design (? Riddles' reverse engineered original Stanier design?) - best wishes for its completion.

[klank]

Hi Stuart

Just to clear up the issue of staying the firebox end of the boiler - I today spoke with GLR about it.

GLR put me in touch with Peter Smith - he does all of the GLR boiler building, flangeing and fittings fabrication for those customers who wish to purchase the Tina boiler as a ready made item. He has built over 60 of them!
He has edited/ added more up to date comments to the text originally contained in Stan Bray's article - these are shown in the current boiler build handbook as now supplied.
He admits that the main plan supplied is that of the original mE 1950's boiler - which is somewhat out of date with current regulations.

Anyway, as regards the need for stays, in all of the boilers he has built for GLR, no additional stays in the firebox have ever been fitted. He agrees that the fire tubes act as stays in the vertical plane but as the water space between the firebox and bottom of the barrel is so small, stays are not warranted.
The boilers he has built have been tested to 250psi in hydraulic testing and steamed to 160 psi. with no problems.
Although the "normal" working pressure suggested is 80psi, for "Tina" and similar slow revving engines, 40psi would be the normal maximum working pressure suggested.
Interestingly, the weight blanced safety valve shown on the plan is now deemed "illegal" under current regulations and must not be used - although a dummy one could be fabricated. A "pop" safety valve is the correct way to go!

I hope this explains the situation from GLR's perspective.
Obviously there is nothing to stop one adding extra rivets in the firebox - as you say - for peace of mind, but they are not essential.

Peter

[lordedmond]

Thanks for the info Peter

at least your mind is now at rest on the subject , But I wish that GLR would bring the plans up to date and get rid of that safety valve

I am still in a quandary as to why they supplied the material for the stay in my kit , although I will fit them when I get round to the build


May I ask you a favour As I have purchased the kit from GLR can I trouble you for a scan of Peter Smiths upto date comments email is in profile


Stuart

[klank]

Stuart - no problem I've got your pm and info will be sent shortly.

Peter

[madjackghengis]

Hi Peter, from the looks of the kit, you've got a very nice build ahead of you.  The quality of the castings and the company show through, even in just photos, and I particularly like the look of bronze in engines of all sorts, but particularly in steam engines.  I am very slowly working on a back burner steam engine, Ajax, from Tiny Power, and will be following this build very closely, as I expect there will be some to learn from it, particularly from the boiler part, as I plan to build one out of an old ET Westbury book, but have never built one before.  Very nice start, and the discussion regarding the boiler is very informative, particularly the answers back from the company, with real numbers as to their own pressure testing standard.   Cheers, Jack

[lordedmond]

Thanks Peter for the amended notes

Although I would take their boiler maker to task with his 250 psi hydro test when the boiler is specced up to be tested at 160 psi WP of 80 psi , to me that is placing unnecessary stress on the boiler and is not needed. thats 90 psi above the design calculations


But as he is a boiler maker I will leave it at that



Stuart

[klank]

Thanks Jack and Stuart.
Good to hear from you.

The big question for me (at a later date) is whether to opt for coal firing or lpg/ceramic burner.

Obviously, the gas firing is simpler, cleaner, much more easy to control (steaming rate and so on) and heat is instantly available.

Coal means a properly fabricated door/ring, a blower, a grate (materials for that are extra), and a much messier and harder to control affaire all round!

BUT - the attraction of the latter - if you are a masochist - is the correct SMELL/ATMOSPHERE, and the chance to make a scale sized shovel etc.
Plus the challenge of the extra fabrication work - maybe make the grate, fire-hole/door etc. anyway and use a gas burner as an option (the fire box sits over the grate) - just swap them over - assuming there is enough gap for gas/air combustion - lots to consider - but I do fancy wielding a shovel and pricker (in miniature).

I'll get some more work done tomorrow on the bed plate and maybe start the flywheel, and maybe post it - today was a non starter - domestic duties call.

Best wishes and respects

Peter

[klank]

I marked out the drilling points on the various pads as per the supplied plan.
I am not too happy about one of them and the adjacent hole for the crank disc - seems slightly out of place according to the supplied dimensions!
It may be prudent, therefore, to leave centre popping/drilling/tapping until later - until the various engine elements are ready for mounting - and see whether more serious attention is needed to the bed.




Flywheel next.

This is how it came in the kit - virtually no flah at all and pretty true, apart from tapering to the wheel thickness at its rim. The bosses were of unequal length, but well within the required dimensional limits and both appeared true to the outside diameter following some quick and dirty work with calipers/ruler.
I was particularly impressed with the condition of the spokes/inner wheel rim - very little to do here.
All in all - a very nice casting.





In Stan Bray's build, he recommends setting up the wheel immediately in the 4 jaw, and tapping it into position using a scribe block/chalk to get it in the ball park.
Given the overall look and trueness of my casting, I decided to go another way, and find the best centre on the longer boss face first.
I licked it over with a file and then scribed a series of diameters with a centre finder, having "blued" the boss face with felt tip pen.





The centre of the cluster of lines, where they crossed was popped. Sorry - a poor photo - not all of the scribed lines show up too well but there was very little divergeance where they all crossed.

(Note - I know all of this is pretty basic for many of you readers, but this somewhat elementary stuff info may be of use to newbs - as a "beginners' engine". No offence meant to anyone who reads this!)





I set up the casting in my 5" 4 jaw - plenty of meat to grip with the jaws reversed.
Using a tailstock centre, and home made wobble bar in the popped mark and a clock, it did not take long to get the casting rotating true around the mark.

(Big apologies - I did not remove my tool post before taking the next two shots - I was in a bit of a hurry, and not thinking "ahaead").





I then used a scribe/block to see whether the inner wheel rim/spokes were running true(ish) in the facing plane.
What a blessing - it ran virtually true with no more tapping around or wedging out the rim.
Even better there were no knobblies/inclusions around the inner rim or where the spokes joined.
All in all, an extremely nice casting by the looks of it.





I used a cheapo brazed/tipped set of tools to start the machining - They are a bit clunky (well they are REALLY CHEAP) but withstand all kinds of abuse and work very well on cast iron.
At this stage, I just worked on the outer rim/face/spokes and boss - brought them to near finished size.





Next up - to bore the centre hole and finish the other side.
The plans show a grub screw fitting for the flywheel on the crankshaft - not ideal. A flywheel should always run perfectly true and I don't like the idea of a grub screw - it might cant the wheel ever so slightly on its crankshaft when tightened, and it can be a weak means of fixing.
I would consider a "coned brass sleeve/set screws and jacking screws" set up normally for an outside flywheel but as this one sits inside the bearings and space is tight, as Stan Bray says, I shall use a slotting tool on the finished bore to make a small keyway fixing.
I shall turn up a stub mandrel for mounting the casting after boring/slotting to do the finishing and outer wheel rim face.

I hope to post a bit more tomorrow.

My sincere thanks to those who posted such encouraging and kind comments.

Best wishes

Peter

[saw]

Nice work I am looking forward for the next chapter 

[Rob.Wilson]

Hi Peter 

All good stuff showing your method of work  ,,,,,,,,,,,,, looking good 


Rob

[klank]

Benni, Rob - thanks.

[NickG]

Peter, I've always liked the look of those GLR engines. Will be nice to watch this come together, a proper working steam plant. 

[klank]

Thank you Nick.

Work in the shop today was somewhat interrupted - s.w.m.b.o. insisted I watched "The Wedding". To be fair, what a joyous day for so many people. Worth watching and wish the couple well.

TIP
Going slightly off topic here, I use the 4 way tool post as supplied with the lathe for the cheapo brazed tip tools - they fit perfectly to exact height.
For most other work, I use a poor man's quick change toolpost (one day I will get a "proper" one - but this does o.k.).
Due to its design (the tool holder hangs over one side away from the tool post itself), the pressure on the tool in the holder, tends to impart a bit of extra "twist" to the tool/ holder, around the post, unless the handle is really done up tight.
I have not seen this tip posted, so will give it here :- for two or three squid, Arc. Euro sell needle roller races, with a pair of thrust washers (top and bottom) to help correct this situation.
I have found fitting one of these sets a real bonus - the cheapo q.c.t.p. now sits exactly where I want it without straining the guts out of the handle. It also works just as well on the 4 way.
 A very well worth investment for such a tiny outlay.
I had better add - I have no connection at all with Arc. Euro, except to say they are a very friendly and most helpful firm to deal with.
I have tried to show the race, minus top washer here :-





And in use, here :-





Now, back to the Flywheel.

Rather than just drill'n'ream, I decided to follow Stan Bray's advice and bore the hole first, just in case the drill goes walkabout.
I centre drilled the hub and ran a pilot drill 9/32" dia through.
This is a tad over the dia. of my smallest boring bar (1/4" dia).
With the boring bar tool tip on centre it is then a case of taking small cuts through the bore to bring it to a tiny bit less than the crankshaft dia. (1/2").







Going off topic slightly, there was a most excellent thread recently (I cannot find it right now) on making a "Y axis" read out for a lathe using a long travel dial gauge. (For us lesser citizens who cannot afford DRO set ups - here's wishing!)
Sourceing a long travel plunger dial gauge, without paying through the nose for it was difficult, but once again, Arc Euro came to the rescue. They do one at quite a modest price compaired to flea bay etc.
I now use this set up for really "important" stuff - I find it much more reassuring to see the dial clock hand move with confidence it is right, rather than try to remember the handwheel collar numbers. (I get too confused at the wrong moment using handwheel collars - let alone making sure backlash is dialled out!).
Anyway, for this operation, I set it up for the boring work.





Now its just a question of following through with a 1/2" reamer at slowest possible revs. (The crankshaft is 1/2" dia).





With heart in mouth (cos there aint no going back), I took the flywheel out of the 4 jaw not forgetting to write down all of the appropriate dimensions I have got to. Essential to make the other side a "mirror" of what has been done. Its very difficult to try and measure rim thickness or some such, on the side facing the chuck if you don't - yes I have done that too often.

I then re fitted the flywheel to the 4 jaw with the other untouched side outmost, using a soft faced mallet to get the finished rim hard up against the inside faces of the 4 jaw. A quick look with the lathe running will tell if the machined face is running true - fortunately, mine was.
You don't have to get it dead centred as all to be done now is face the outside of the boss/hub, and bring it to length.

I then turned up a stub mandrel from a length of 20mm mild steel bar. Allow sufficient to hold in your 3 jaw - or I used a collet.
Once this operation is started, the mandrel must NOT be moved form its location - make sure it is held in TIGHT!
All to do with keeping everything concentric at this setting. (Trying to avoid a wobbly flywheel).

Turn down sufficient length, slightly less than the thickness of the flywheel to exactly 1/2" dia. - the thickness of the crankshaft - or better still, keep offering up the flywheel as the turning down proceeds. You need a very good, slop free fit. Leave a good accurate shoulder inboard.
I turned down the end, allowing for the thickness of the flywheel, plus a bit, to 10mm dia, and I threaded this M10 using a tail stock die holder.
The flywheel can now be gripped with a washer and pair of nuts on the mandrel, leaving all of the untouched face plus the rim to be machined without further re-setting.
Here's the stub mandrel.




Just an observation, machining cast iron without suds/coolant makes the casting extremely HOT!!
I suppose coolant/suds could be used, but the clearing up afterwards is disgustingly messy - thick black gooey sloppy muck everywhere. (Done it once - not again unless I have to).


I am very conscious that all of this is very basic to many, but as I said earlier, I am trying to write this for a beginner.
If anything is wrong or dangerous - please shout, 'cos I am learning too - but be kind!

Best wishes,

Peter


 

[saw]

Good work 

[sbwhart]

Well shown Peter 

Stew

[klank]

Thanks Benni and Stew.
I'll try and keep going tomorrow.

Did anyone notice my first (deliberate - ha ha) mistake?
I could have, maybe should have, cut the slot for the flywheel keyway fixing, after boring/reaming, whilst still set up true in the 4 jaw.
Oh well, I shall attend to that later.