A Tandem inverted V twin paddle engine

[John S]

The latest creation of a warped mind is a tandem inverted V twin engine using two of the Chiltern Steam engines. No gearing to the paddle shat in mind but direct drive to the at resent 150 mm feathering wheels with seven floats 65 mm x 25 mm.  The hull is 1300 mm long by 200 mm beam and draught of 90 mm and is effectively a stretched Strongbow hull enlarged to fit a decent sized engine and boiler. The boiler will either be a 108 mm diameter vertical with 27 8 mm fire tubes or just to be different a boiler based upon a Sissons return tube boiler with off  set furnace  simply because I have not seen a model with anything like it . The engine itself has 14 mm bore cylinders and 18 mm stroke so has four double acting cylinders. Firing is gas with automatic boiler feed and pressure control and in view of the actual power output I may re-make the wheels to a larger diameter and increase the depth of the floats which are limited to 65 mm widths. Not yet decided is whether to link the engines together or fit a servo to control each engine valve Better add some engine photos. John.

[JonCameron]

I'll await updates on this project. It's quite a large project for sure.

I'm confused on why you'd want to drive the engines independently, surely having the cylinders working together would be more efficient? I've possibly mis understood you. For the boiler dimensions you mention, there was a Sentinal locomotive which I have the magazines for. That used a 4" diameter boiler, driving a Stuart twin vertical. Although coal fired, (just ignore anything below the grate level), may prove useful if you think it would be of any help to you.

Regards
Jon