Southworth Corliss Engine.

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I am 'considering' one as my next build. - Nice and big and lots to get my teeth into and I do realise that this would be a considerable time investment.

But.!!!!!!!! ............. This is not a simple engine now is it.? The basic engine is, but there it ends as the whole point of a Corliss is the unusual valve gear and the way it is linked to the governor. Looks critical and far from simple.

I have browsed the web and found several build threads for this engine and seen some truly spectacular model engineering of a standard that I could only dream of reaching of this model.

There are several configurations of the basic design as I am sure many are aware of and I have not reached a stage of deciding which one I might construct.

Since I started model engineering I have made Stuarts James Coombes engine and their No.4. Both of which I am reasonably pleased with. But this one would be on a whole different level of size, complication and build duration.

With such limited construction experience do you think I would be biting off more than I could chew.?

I don't mind a challenge. In fact I welcome it, and to many here I suppose that is a large part of the appeal of model engineering. But I need to be realistic and not set the bar so high that I would have no chance of success.

Please be honest. You will not offend me.

Cheers, Nick

My advice to you would be to give Bob Potter a ring and talk to the man who can give you the best information available, Bob took over from Peter Southworth and you will find his contact details on the website.

Phil

That postman is going to need a big van!

Depending on which configuration you go for these engines can take up a serious amount of space so displaying and storing them can be an issue, you would need an area about the size of an A2 sheet for some of them.

Another thing to think about is although they are big engines there are a lot of very small parts so think about whether you want to be playing about with small items or if you would rather have a chunkier engine.

If its a corliss you want then there is a barstock one about that can be built into a very nice model that you would think was done from castings. Also Anthony Mount has quite a large design that only uses two castings with the rest being fabricated or cut from solid.

J

Nick,

You might want to consider a design by Anthony Mount, The Fenby Corliss engine serialised in Engineering in Minature starting November 2012. The advantage with this design is that you get all the words & music how to build it.

Regards

Luigi

Edited By Halton Tank on 23/01/2016 17:58:26

Nick,

As Jason said it is not a small model and it takes a fair bit of real estate. I guess it can be scaled down but the small parts of the Corliss valve linkages become even smaller and more fiddly to do.

I guess, at the end of the day, it all depends how authentic you want the model and how much time you can invest in it.

Vince

Vince is far to modest to link to it but have a look at his version of the ModelEngineMaker Corliss engine here.

Wonderful! Build log here

Plans here

Rod

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Impressive. Very, very impressive.

Nick

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If I were to 'attempt' one of these it would be the tandem compound. i.e. long and thin, not long and fat like the cross compound or the twin.

Maybe an idea for me if I go down this route is getting the drawings and try making the valve gear first. That way if it proved to be too big a slice of cake for me I would only be out the cost of the drawings and time.

While on the subject of model compound engines. Is it true that when running on air that the LP cylinder does not 'really' do anything as the compressed air has exhausted it's energy in the HP section. It is only when the expansive qualities of steam (and at higher pressure) are applied that the LP section starts to work and produce extra power.? This of course does not matter for a model that is just turning over for display purposes. - Just curious.

Nick

Lovely to watch, almost therapeutic

That's right Nick you don't get any expansion when running on air so could really make both pistons the same size and run it as a double high but still keep the outside the right size.

So its the valve gear you are interested in

If space is an issue you could always do a vertical Corliss

Beautiful model, but it doesn't appear to have trip gear. I know it has little benefit when running unloaded on air, but it is a shame not to have the click click sound

Its not just the expansion of steam that is to be considered on the low pressure cylinder, if a condenser is also fitted (as it is on my model of "Agnes" then there should be a vacuum helping to pull the piston along as well.

Again on the model this will not be something I am intending to make work as in full size, as it will only ever run on air, so externally it will look the part, but nothing much will be going on inside.

In fact on the full size Agnes she only runs at a very low pressure in the museum, and the condenser is not actually linked up either, so they have to run it with the low pressure cylinder on full steam ie no cut off, otherwise it acts like a big vacuum pump and fights the high pressure cylinder.

Not wanting to criticise Vince's super model, I do agree with Duncan that the clicking of the trip gear makes a Corliss engine, most model engines are a right begger to get running as quiet as Vince's but it is too silent for my personal taste.

Phil

Edited By Phil P on 24/01/2016 17:34:14

Nick this is the Fenby as suggested by myself and Luigi, complete with clicks and it goes chuff chuff

Edited By JasonB on 24/01/2016 17:38:59

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Well.!

Another member kindly sent me some photographs of the drawings to give me an idea of the depth I would need to go to for construction.

I think I can now safely say that this would be biting off more than I could realistically chew.

Thanks to all those that replied.

Cheers, Nick

I might be able to find you a nice wobbler design instead

It does look a bit daunting on the drawings and is certainly a long term project but I should think you could handle most things there. As I said earlier its a big model but does have a lot of small parts rather than a big model with less larger parts.