Minimum equipment for TE build

[William AyerstParticipant @williamayerst55662]

I'd all but decided on a G3 or 5" Gauge loco as my next project, but while I was idly browsing the internet I came across myfordboy's traction engine build – which seems like a fun medium-length project: Link removed see C of C

I wonder if this might be a fun project to get more experience before really dumping my time into a multi-year project – but I'd realised I'd not really considered the requirements for a TE build.

I currently only have my ML7 with the vertical slide and so from what I gather there is a serious equipment deficit for any size TE – i.e. the need for an dividing head for cutting gears, and more likely a mill?

While I was looking into this I saw that the Minnie comes up alot and I realise that is a much bigger project overall, but thought I'd ask anyway – is it likely to be significantly 'better' ? Neither can pull you around and both appear to have similar machining requirements?

 

Edited By JasonB on 16/03/2021 07:02:33

[William AyerstParticipant @williamayerst55662]

[Nigel Graham 2Participant @nigelgraham2]

Ostensibly a locomotive is simpler than a traction-engine despite (usually) more wheels and effectively two engines propelling it; because it does not have gears and the boiler is not also the chassis. Nevertheless, both a 5" gauge loco and a "Minnie" are big steps up from Myfordboy's neat little engine, which is within the scope of Myford lathe.

People have built successful, small-scale traction-engines and 5" -g locos with a fully-equipped Myford 7 or similar lathe, including with a dividing-head suited to the lathe, a bench-drill and hand-tools; but the feasible scale is very limited and milling anything of any size using a vertical slide must be something of a challenge.

Ideally you do need a milling-machine as well as a lathe if you intend making anything of a reasonable size.

Also, do you have the means to make the boiler?

You'd have to consider, as you suggest, how and where you are going to drive the completed engine. I think the Minnie will just about draw a suitably free-running trailer with its driver, on a hard, level surface – I don't know if it would do so on grass much rougher than a bowling-green. Only I can't imagine a bowls club letting you try it.

[JasonBModerator @jasonb]

The Minnie is a far more complex engine than Myfordboy's which is just a step up from a Mamod.

The original Minnie was built on a Myford and the one in my Avitar on a similar sized Emco lathe with just the vertical slide and a small 4" rotary table.

[William AyerstParticipant @williamayerst55662]

Thank you both – I think a mill, linisher, and drill press are in my future, but I think I would really like to get more experience with model engineering before dumping more £000's into the equation. I now realise the advice to get the biggest lathe I could handle was spot on – I'm already thinking that a few extra inches of swing would be useful – and I don't want to make that mistake with my (future) mill – so it will likely be a costly purchase.

I'll ask about the dividing head/rotary table in the tools subforum, thank you.

Nigel, one of the things I'm coming to realise about ME is that there's no NEED to make things as small as humanly possilbe, which coming from small scale model railways is quite a challenge. The idea that I could make a TE (or locomotive) that COULD pull me, or a kid, around as opposed to just sitting on the shelf is something I'd not really come across. I think there are better 'shelf' models like the various Stuart beam engines, so if it's going to be a vehicle it'd better work. I had originally considered a Fowler Z7-style ploughing engine until I realised the huge radius of the cuts required

JasonB, thank you for the tip re: work on a Myford. I'm not sure if spending £150 on a rotary head to fit it is going to be money down the drain if a larger mill is in the future, but I will definitely bear that in mind. From my understanding, I have to be aware that the diameter of the boiler needs to be fly-cut off the bottom of the cylinder casting – which for a lathe means a swing of boiler dia + total height of cylinder, right? I'm not sure about the wheel construction on TE's – presumably I'd need to turn those also? i.e. on the ML7 a max of about 8.75" dia?

[SillyOldDufferModerator @sillyoldduffer]

Can't advise about Traction Engines in particular but I guess we all approach new projects in much the same way by studying the plans, or a real one, and asking 'how could I make that, or can I buy one', 'what tools do I need', 'where can I get the materials' and 'have I got enough money, time, space and the necessary skills?'

With time and skill it's possible to make many objects with hand-tools only, but the process is painfully slow. Of course there are jobs for which bought tools are all but essential. Of these a screw-cutting lathe is the most important, and – maybe with some ingenuity – they can be used for dividing, slotting, drilling, precision boring, lapping, milling and other operations. Huge but! Although lathes can do lots of stuff, specialist tools like milling machines, pillar drills or shapers are far more convenient. The guy with a big workshop full of tools will run rings round modellers who have nothing but a Super Adept under the stairs simply because he saves so much time.

The size of the finished object is a consideration. For example, the swing of your lathe puts a limit on the maximum diameter of any wheel cut. Likewise the spindle bore and length of the bed restrict what can be done.

In my general purpose workshop (bandsaw, grinder, bench+vice, mill, lathe, compressor and hand-tools galore), I probably have the wherewithal to tackle a small traction engine already, apart from the boiler. I don't have a big enough torch or the requisite skills to make one without spending a fair amount of dosh on gear and then learning how to use it properly. My best bet is probably to have the boiler made for me.

As hobbies go, model-engineering isn't outrageously expensive, but finding the cash is difficult enough to slow most people down. I guess most model engineers build their workshops and skills up over time, not with a big bang. As usual much depends on the individual. I like to take things slowly, buying tools as and when needed, saving up if necessary, and slowly learning my trade by starting simple and gradually tacking difficult work in graduated stages. Others like to jump in at the deep end and are motivated by overcoming serious challenges. Over-confidence has been the ruin of many a prospective engineer. Workshops full of abandoned projects, money and time down the drain, and total demoralisation of the enthusiast.

My recommendation is to start small with something like Stewart Hart's Potty Mill Engine. Actually making things is a valuable teacher. Suddenly the need for other tools and new skills becomes obvious, as does a feel for how long work is likely to take in your hands. I reckon Jason works at least times faster than I do and gets a better finish. Can't blame my tools, we have similar equipment…

Dave

[JasonBModerator @jasonb]

It's only the radius that matters when doing the underside of the cylinder and chimney saddle so they can be done on an angleplate on the cross slide so ctr height is not an issue as you do them on their side.

Minnie rear rims are 6" dia so easily done even without a gap bed, some other larger designs use rims that are finish cast so don't need turning or are made from rolled and welded steel so don't need turning. Flywheel and final drive gear are usually the governing diameters.

Edited By JasonB on 16/03/2021 08:31:37

[JasonBModerator @jasonb]

If you are thinking of buying a mill then that makes a very good drill press so you don't really need a drill press on your list unless it's a cheapie stop gap until you can get a mill.

have a read of this pdf and then keep changing the issue number in the url to get the rest of the Minnie series then that will give you an idea of what's required.

[William AyerstParticipant @williamayerst55662]

I have definitely found that making the bits and bobs that I've done so far to be a far greater teacher than reading books, but only to a certain extent – knowing how to approach something is required, then actually trying is where the learning happens. If you can't get that far you're just stuck aren't you? That's why I'm so grateful for this forum

feel like having completed Tubal Cain's "Elizabeth" and hopefully my 10V soon I want to move onto something larger and more complex – but a piston valve engine I can build on my lathe could be very handy so I've asked Mr. Hart for his plans. In the same vein as a fabricated piston-valve engine, I had been recommended the Bogstandard Paddleduck as a well thought out design.

With regard to the Myfordboy TE – I'm checking with model engineer's laser if they can cut the gears, and had a nice chat with hemingway about the Thomas VDH kit – so lots of options available and I'll wait to hear back. Mr. MyfordBoy has also kindly sent me the gear sizes and I've calculated the ratio and meshing distance but can't seem to find anywhere to buy pre-made gears…

JasonB thank you for the tip on the drill press/mill thing – you're totally right. Thank you for the PDF link.

[Harry WilkesParticipant @harrywilkes58467]

Posted by JasonB on 16/03/2021 07:06:57:

The Minnie is a far more complex engine than Myfordboy's which is just a step up from a Mamod.

The original Minnie was built on a Myford and the one in my Avitar on a similar sized Emco lathe with just the vertical slide and a small 4" rotary table.

I believe but stand corrected if necessary L.Mason claimed the engine could be built just with a lathe and drill press.

H

[Nigel Graham 2Participant @nigelgraham2]

…but can't seem to find anywhere to buy pre-made gears…

Not to the specific pattern for a particular engine, no, but you've a chance if they are to regular DP or module sizes and tooth-counts.

For there are transmission-components dealers who sell stock gears, usually made with hefty great bosses, keyways and grub-screw holes, but cut in a machinable steel so capable of being modified if necessary for the application.

Many industrial gear users now use this approach, rather than cutting their own wheels. It's cheaper, without sacrificing quality!

[not done it yetParticipant @notdoneityet]

Many gears can be cut just using a lathe – no mill and no rotary table involved. I know of at least one youtube channel where the you-tuber has demonstrated making gears with his lathe.

[JasonBModerator @jasonb]

As Nigel says you can get off the shelf gears that can be modified. HPC will have the DP gears which are wide enough to give you two to the thickness required if sawn in half and faced to thickness.

Slightly cheaper would be to use imported metric gears from someone like Beltingonline, again thick enough to get two for one. 1MOD would works out just about right if you used 76T & 15T rather than the 72T & 14T of the 24DP size.

Both options probably cheaper and better than laser cut

[David TocherParticipant @davidtocher94033]

I followed JasonB's link (16/03/2021 09:59:51) and tried to look at the .pdf files but #3385 and #3402 onwards are missing which is a pity. Is the book just a reprint of the ME articles or is there more?

Edited By David Tocher on 17/03/2021 18:47:41

[JasonBModerator @jasonb]

3401 is the last part.

Book is basically the same content

[David TocherParticipant @davidtocher94033]

but #34385 is missing. Any chance it can be made available?

[William AyerstParticipant @williamayerst55662]

Thank you very much for the link, JasonB – I've got some reading ahead of me.

Using this site (https://www.mechanicdrive.com/spur-gear-calculation) for Myfordboy's TE I get:

72/24DP = outside circle of 76,176mm dia
14/24DP = outside circle of 14,812mm dia
Centre distance 45,494mm

Using 75 and 15T 1Mod gears I get:

75/Mod1 = outside circle of 75mm
15/Mod1 = outside circle of 15mm
Centre distance of 45mm

So that really is perfect.

Unfortunately both belting and HPC are charging £19+ for the larger gerars and I'm not sure I can cut a 76mm gear in half lengthways! I think rather than £60 on gears I'd rather spend £150 on the VDH or £120 on an off the shelf rotary table/DH and make my own going forward!

[JasonBModerator @jasonb]

Think I meant to write 75 & 16 T which will give just 0.004mm error that can be taken care of by depthing the gears.

Cutting the gears is all good hacksawing practice I've done it with quite a few commercial gears as they are often far too wide for the majority of model designs.

 

Edited By JasonB on 17/03/2021 20:03:48

[William AyerstParticipant @williamayerst55662]

Just for the sake of argument how would I go about facing them? A superglue arbor or something?

[Michael GilliganParticipant @michaelgilligan61133]

Posted by David Tocher on 17/03/2021 19:07:18:

but #34385 is missing. Any chance it can be made available?

.

[ assuming that you mean #3385 ]

Check the series part numbers XXV and XXVI appear either side of that issue.

If I recall correctly, many ME series proceed in alternate issues.

MichaelG.

Edited By Michael Gilligan on 17/03/2021 20:18:06

[William AyerstParticipant @williamayerst55662]

Checking the Minnie articles just for the sake of completeness it would appear that the final drive is 2.8" dia – so more than doable on the ML7 as you have rightly said, cheers!

I think if I'm going to build small, the MyfordBoy engine makes more sense – if I'm going to the trouble of building something complex, it may as well be bigger – at which point maybe a 2" scale model and blagging the help of some local engineers for the smokebox/cylinder/wheels

Edited By William Ayerst on 17/03/2021 20:28:22

[Nigel Graham 2Participant @nigelgraham2]

Facing them: you could use a superglue arbor, and the worst likely to happen if the tool digs in, is the glue shearing.

Alternatively use an arbor that mimics the shaft it will fit on the engine, and holds the gear in the same way.

I have tackled a similar task recently by holding the component to the faceplate by screws tapped into holes in it – but this was a part that either had four holes in it anyway, or their inclusion made no functional or aesthetic difference to the finished part.

As a guide, an ML7 faceplate is 9" dia., and the T-slotted saddle turns the lathe into a small horizontal borer for bulkier lumps such as the smoke-box and cylinder.

[not done it yetParticipant @notdoneityet]

I'm not sure I can cut a 76mm gear in half lengthways! I think rather than £60 on gears I'd rather spend £150 on the VDH or £120 on an off the shelf rotary table/DH and make my own going forward!

Think positively. Start the cut with a slitting saw, thin grinding disc or a parting off cutter with the gear running true in the lathe. You would have less than 30mm depth to saw with a circumferential guide to help keep your blade straight. I’m quite sure I would not relish cutting a 75 mm round, in steel, with only a handraulic hacksaw, mind!🙂

I, personally, would bolt it to a longer length of bar and use a mechanical saw, probably after starting the cut accurately in the lathe.

[Paul LousickParticipant @paullousick59116]

If there are only a few parts that are too big for your mill or lathe, you could do them somewhere else. Join a model club and members will normally help you.

I did not want to make my own gears and bought them from a model supplier company. The engine is 6"scale and some parts were too big to do in my home workshop and did them elsewhere. For example, the rear wheels are 24" diameter and I had the rings rolled at a local engineering shop, fabricated them in my workshop and had machining done in a commercial shop.

Paul

[JasonBModerator @jasonb]

Posted by William Ayerst on 17/03/2021 20:04:42:

Just for the sake of argument how would I go about facing them? A superglue arbor or something?

bought or homemade softjaws are the ideal thing for that and unlike an arbor will allow you to face the whole surface.

A few spare halves from gears that were thicker than needed, more have been shared with people making the same engines. Unless your hacksawing skills are really off then as the MB gears are quite thin you will not get into trouble if the saw wanders a bit so no real need for staring with a parting tool. Just leave the gear in the vice and saw it in several sessions while working on something else

Edited By JasonB on 18/03/2021 08:19:12

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