First project

[Ian AnthonyParticipant @iananthony10016]

Hi Everyone,

I'm looking for a first project and am thinking about an oscillating steam engine. I have been looking at the one on http://www.steves-workshop.co.uk. I've also looked at some of the threads on the forum that relate to it. However, I think I'd like to make something a bit bigger with an 8 inch or possibly larger flywheel and a horizontal cylinder. I have three questions:-

1. Is this going to be too ambitious ?

2. Can anyone point me in the direction of a suitable design and drawings ?

3. If nothing like this exists, would I be safe to design my own (early in my career I was a design draughtsman) and could I just scale everything up, including the port sizes etc. ?

I have a new 10 x 20 lathe and have some basic competence in turning and milling gained many years ago. I've already turned a few simple items and can't wait to get started on a proper project.

Many thanks in anticipation.

Ian

[Ian AnthonyParticipant @iananthony10016]

[IanTParticipant @iant]

Something along those lines would be a very good introduction Ian.

I would think a book such as Tubal Cains' – "Building Simple Model Steam Engines" will help you choose something suitable – and frankly it's much better than just leaping into anything really complicated – and not too expensive if you make a mistake (or two) along the way. Once you feel a bit more confident – there are always more ambitious projects/casting sets to look at later.

Regards,

IanT

[JasonBModerator @jasonb]

Most of the designs for these simple "wobbler" type engines tend to be on the small side as beginners don't like to risk laying out for big bits of metal or have the capacity in their machines. The larger oscillating engines tend to move away from the simple valve arrangement as per the one on Steves site and have slide valves operated buy various forms of linkage and eccentrics which all start to become more complicated so are not ideal for the beginner.

You could have a look at something like this which is a horizontal design not unlike that of Steves but is does have a double acting cylinder (steam pushes piston both ways) so will be more powerful. If upped by say 50% you could run it with an 8" spoked flywheel which would have a similar effect as the now 6" one to the drawings. The main base would be better built up from 3 pieces of plate rather than carving from solid but otherwise should be doable.

You could scale up steves design and lay it on it's side but I would look for a double acting one rather than single.

 

J

Edited By JasonB on 12/02/2018 17:39:45

[BazyleParticipant @bazyle]

You might consider first finding a nice looking flywheel and making the engine to match it.

[RedsetterParticipant @redsetter]

I would agree that many of the engines aimed at beginners are too small, and it is it not always realised that oscillating engines need to be very accurately made if they are to work properly.

A slide valve engine is no harder to make than an oscillator, although as it has more parts it will take a bit longer. That said I would not recommend the usual small Stuart engines to a beginner – they are very fiddly and you certainly won't be a beginner by the time you finish. Something a bit larger is really a better choice.

I built a vertical engine based on Westbury's Trojan design and found it a lot easier than the Stuart S50 which I did next. Westbury's drawings were good, the only casting needed was the cylinder and even that could have been fabricated. I thought at the time that a double sized Trojan would be a nice project.

To answer your basic question, yes you can certainly design your own!

[Jim NicParticipant @jimnic]

Ian

I can recommend Steve's wobbler design as a first project, it was the one I started on.

There is a lot of good guidance with the drawings if your skills are a bit rusty and if you are up to speed already it will be good practice to get familiar with your new lathe. As no castings are involved, if you make a mistake there is no delay in making a new part and it will be cheaper than replacing a casting. Plus you will hopefully end up with some bits of stock materials which always come in handy.

My second engine was a Stuart 10V which I did with no problems because I had a fair knowledge of my machines and how various metals behaved by then. I also had a few more bits of tooling having completed a couple of other small projects.

Jim

Edited By Jim Nic on 12/02/2018 19:14:37

[DanielParticipant @daniel]

At the risk of reappearing as a complete idiot,

what is a 10 x 20 lathe ?

TIA,

Daniel

[David Standing 1Participant @davidstanding1]

Posted by Daniel on 12/02/2018 22:20:15:

At the risk of reappearing as a complete idiot,

what is a 10 x 20 lathe ?

TIA,

Daniel

 

It means it will take a 10" diameter workpiece, and is maximum 20" between centres.

 

 

 

Edited By David Standing 1 on 12/02/2018 23:26:17

[JasonBModerator @jasonb]

Or for the metrically minded 250mm swing and 500mm between ctrs. Eg the Warco 250

[DanielParticipant @daniel]

Thank's for clarifying that

[David Standing 1Participant @davidstanding1]

Posted by JasonB on 13/02/2018 07:29:38:

Or for the metrically minded 250mm swing and 500mm between ctrs. Eg the Warco 250

It was an imperial question Jason.

Clear outta here, and take your Johny foreigner measurements with you

[mechman48Participant @mechman48]

Posted by David Standing 1 on 13/02/2018 22:54:55:

Posted by JasonB on 13/02/2018 07:29:38:

Or for the metrically minded 250mm swing and 500mm between ctrs. Eg the Warco 250

It was an imperial question Jason.

Clear outta here, and take your Johny foreigner measurements with you

Now now girls, behave yourselves; it's only our country cousins across the pond that still work in imperial, just remember it's we Brits that can convert from one t' other with relative ease…

George.

[JasonBModerator @jasonb]

David, if it was an imperial question why did you not give the answer in ctr height as is the old English way

Besides Ian the OP has a Warco WM250, had he had a Chester DB10 that would have been a different matter

But most importantly Daniel is from Framce so would understand Metric better and not appreciate some of the comment.

Edited By JasonB on 14/02/2018 07:33:05

[Ian AnthonyParticipant @iananthony10016]

Thanks to everyone for all the advice and information. It's given me plenty to think about.

With regard to the metric/imperial argument, when I was at university back in the 70s I had an enlightened lecturer who said that when us students got out into industry we would encounter both systems and hence we had to understand how to work with slugs as well as kilograms, poundals as well as newtons etc etc. Of course he was absolutely correct and did us all a great favour. When I packed up working in aerospace a year ago I was still using feet (for altitude) knots (for speed) and so on. Unfortunately the younger engineers in my charge had only ever worked with the metric system so found this difficult. Now I have a metric lathe and imperial micrometers and vernier thus carrying on a proud tradition !

Thanks again for all the help.

Ian

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