Hello from the other side of the pond

Hello group:

Much woodworking done, not a lot with metal. Looking at a project to fill out my approaching retirement and have selected a model open steam launch. Time won't be an issue, equipment may be. I'll have a lot of questions about the lathe/mill work and the capabilities of my little unimat. Really like the Stuart twin steam launch combined with my own boiler build. I'm roughing out the conceptual design and layout and will post questions in the appropriate sub-forums. I hope I can get around buying a larger lathe, just to avoid my wife throwing the uni at me. It's small but heavy...ouch.

I couldn't hold off. First dumb question:

Can a cast iron Stuart Engine cylinder be hand bored? If I need to I'll post it in the appropriate sub-forum. I ask this because the first rifles had hand rifled barrels, somewhat of a similar process. Possibly using a reamer?

Regards,

Ken S.

NYC-USA

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It can be done by hand but would not suggesting for a first project luckily it should not be a problem for a Unimat SL or Unimat3. I made my first engine, a 10V on a U3.

Welcome Ken and please remember that there are no dumb questions; only questions that one doesn't know the answer to!

I believe that Stuart castings can be bought ready machined so that might be worth a thought.

Brian

Welcome to the MEW asylum Ken.

... I believe that Stuart castings can be bought ready machined so that might be worth a thought... +1, check out Stuarts catalogue / website

... It can be done by hand but would not suggesting for a first project... +1

I would suggest you start with a Stuart 10V, a nice little engine to get used to making crank shafts & setting up timing. Have a look at mine...

https://youtu.be/pjTwELRUSiU

George.

Edited By mechman48 on 01/06/2017 11:08:55

Ken. re. above, tried embedding vid as never had much success before... this time...

George

No Problem George, just need to sort that Neil out about rotating photos now

Hello Group:

Thank you for all the replies. Would be interested in how to bore the cylinder on the Unimat. Vertical mill? I looked at Stuarts website but they did not have a machined twin steam launch. I'm in no rush and will be joining the boat forum to get some ideas on hull design, size and configuration. Thanks again for the warm welcome.

Ken S.

NYC-USA

A single cylinder or the D10 could be done with the 4 jaw chuck but with the twin being longer it will hit the bed as you swing it. I think I would be inclined to do the boring by mounting the casting on it's side ontop of the cross slide and using a between centres boring bar. Probably means having to make a small subplate as the standard milling table would put the bore too high.

An alternative would be to ditch the cylinder casting and make your own - basically two short "tubes" for the ctual cylinders with a flat plate top an dbottom that they fit into and two blocks shaped to teh curve of teh cylinders each end to form the valve ports. Have a look at this thread to see how a similar singel "casting" was fabricated for a D10 engine.

Worth reading the whole thread through as it covers the build of the launch, boiler and all the other parts needed to run a marine steam plant of the sort of size you will be looking at.

There are also plans for simple self starting/ reversing, 2 cylinder oscillating engines that could easily be machined on a small lathe.

I believe that there are plans for a complete marine steam plant (boiler and engine etc) available from hobby store.

I guess it just depends on whether you would like to wade into a more authentic slide valve twin or paddle round with a simple engine first.

Phil H

Jason and Phil:

Thanks for the info. Jason I started to look at the message thread you provided a link for and it answers many questions. Some of which I haven't even come up with yet. Phil I'll definitely give a shot at looking up some plans. Guys thanks for the common sense advice.

Regards,

Ken S.