Flash Steam

[aussie bruce]

Well i have looked around for long enough and will bring you up to speed so to say on my latest engine.

I am a member of a model boat club here in Melbourne and obtained a model hull from the swap meet a couple of weeks ago, now the original boat was fitted with a Stuart Sirius engine and flash boiler

Well needless to say most of the interior was gone hence the need for a 1" x 1" single acting twin

So during lunch time at work i have started to design up the engine and build it.

It is too be known as the Flash RHS engine because that's where the crankcase came from.

A piece of 65 x 65 x 3 RHS is the crank case

Valve gear will be a rotary cam as per the westbury design of Gemini re worked with a belt drive

So here goes any thoughts ? Queries? or brick bats ? all to be taken gratefully and with good will

Yes Photos to be added ASAP

Bruce

View attachment Screen Cap.doc

 

[bearcar1]

Well Bruce, that certainly looks very similar to the Sirius from Stuart. A good start to work from.

BC1
Jim

 

[RobWilson]

looks good Bruce are you going to build a flash steam boiler?
Rob

 

[Maryak]

Bruce,

With the cranks at 180 deg the engine is not a self starter. Don't know if this is important for your operation but seemed worth mentioning. For self start cranks at 90 deg.

Best Regards
Bob

 

[tel]

Trouble is, Bob, that with those Sirius type engines (single acting vertical twin with the valve drive brought up from the crankshaft) it is almost impossible to arrange a valve drive for a 90° crank - leastwise, I could never nut one out (ask me how I know this ;D) short of putting individual valves in, with a drive at each end.

 

[Maryak]

Thanks tel,

Another useful piece of info. :bow:

Best Regards
Bob

 

[aussie bruce]

Thanks for the comments gentlemen

Firstly Rob yes a flash steam boiler is on the way just waiting on the tube to arrive off the back of a truck

1/4 and 5/16 316 SS tube 6 metre lengths Firing is to be Gas first then something a little bit more power full I haven't decided yet.

Maryak yep staring will be either by rope or a chicken stick in the prop, I like my fingers and would like them to stay there :big:

Tel bang on the money there i don't like guide rods bell cranks etc sooo after some reading (and i do have access to a very comprehensive library : i have decided to go the Gemini design IE rotary overhead valve just updated with belts and pulleys for your intrest i have attached a scan of the two designs that are interesting to me

must go only 15 minutes till lunch time ends and need to get the cylinder block carved out

Bruce



View attachment 3671_001.pdf