Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: steamshed on November 17, 2013, 04:49:49 pm

Title: Steam Engine Identification
Post by: steamshed on November 17, 2013, 04:49:49 pm: Hi All
Does anyone know what make of engine this is please, I estimate it to be 1/2" bore (not had Cover off yet).Size 3-1/2" long 4" tall
Cheers

Mike
Title: Re: Steam Engine Identification
Post by: AlexC on November 17, 2013, 05:07:00 pm: Looks like 'Borderer' by John Bertinat... castings and plans available from 'Reeves 2000'

Nice engine.

Best regards.

AlexC.
Title: Re: Steam Engine Identification
Post by: Circlip on November 17, 2013, 05:40:49 pm: If cylinder head covers are full circles - Borderer. If they have flats on faces adjacent to each other - Marcher. Latter was a smaller version of former, so were the bore centres which necessitated the flats.

Regards Ian
Title: Re: Steam Engine Identification
Post by: ooyah/2 on November 17, 2013, 05:46:41 pm: At 4" tall it's a Borderer x J.P.Bertinat and can be made as 1/2" to 5/8" bore and stroke.
Either slide valve or piston valve, this one is slide valve.

Also at 5/8" bore the top and bottom covers require a small flat

Nice example of the engine.

George.
Title: Re: Steam Engine Identification
Post by: Circlip on November 17, 2013, 05:57:33 pm: Wots the bore centres George? haven't got the scans on this computer.

Regards Ian.
Title: Re: Steam Engine Identification
Post by: steamshed on November 17, 2013, 06:52:53 pm: Hi All
Yes it has the flats on top and bottom covers, now have to pair up with a boiler and find the right hull for it.

Many Thanks for all the info.

Mike
Title: Re: Steam Engine Identification
Post by: ooyah/2 on November 17, 2013, 08:29:44 pm: Quote from: Circlip on November 17, 2013, 05:57:33 pm
Wots the bore centres George? haven't got the scans on this computer.

Regards Ian.

Hi Ian,
The centers shown on the booklet that is available on the build is 1.125".
What I never could understand when I built mine from stock material is the 1.062" from top face of cylinder to bottom face to accommodate either 1/2" stroke or 5/8" stroke so it was a mater of working out from piston thickness + the 1/32" register top and bottom + the steam gap of 1/32" top and bottom to establish what the cylinder thickness would be..
So the swept volume of the cylinder in a 5/8" stroke engine with a 1/4" thk piston would be 5/8" stroke + 1/4" thk piston + 1/8" for the register and clearance top and bottom would be 1" but that does not include clearance for the nut on the piston head.
From memory I fixed the piston to the rod as per Stuart D10 without the nut, if it wasn't so cold and wet I would have gone down to the work shop to check the drawing that I worked from making the engine 5/8" bore x 5/8" stroke and it was piston valve.

Hope this helps
George.
Title: Re: Steam Engine Identification
Post by: Circlip on November 18, 2013, 11:42:11 am: Yes, 1.125 (1 1/8") ctrs for Borderer and 7/8" ctrs for Marcher.

Looks like builder bought the cylinder and baseplate castings and winged it for the rest. Valve eccentric buckles single clamping screws and main bearing blocks?

Regards Ian