Annoyance defeated

[SignalFailure]

I built one of Elmer's 'rotary valve' engines some time ago but it wouldn't run at all on my 5 psi aquarium pump and not much better when hooked up to my car type footpump. Annoying

I came across a model on the workbench miniatures site recently and decided to try another one - as my gear is all metric there wasn't much point buying the plans so it was an eyeball only project (using Marv's example on that site as a reference image).

Anyway, after 2 days of tweaking the valve timing I finally got it going on the footpump (the clacking noise in this short video ) It isn't anywhere near finished (held in a G clamp in the vice as no base has been made yet) and is covered in off-the-shelf fasteners. Not sure if I'll bother to finish it now, I just wanted the thorn out of my side (only Stirling engines are defeating me now ;D )

I've drawn up metric plans for the major bits (i.e. everything but the connecting rods/forks) - if anyone wants 'em just shout.

A possible tip for anyone attempting this type of engine: make the exhaust flat on the shaft close to half the shaft diameter - I started off with 1.5mm (1/16") deep flats but making the outlet flat just over 2mm deep did the trick.

[ame]http://www.youtube.com/watch?v=DFgVmqpsDJo[/ame]

 

[bearcar1]

Hey hey!! Glad to see you finished up your project Paul. Nicely done (store bought fasteners and all ;D) I can hear the foot pump in the back round but whomever is doing the stompin' sounds like they are about to have a coronary :big: :big:

Cheers

BC1
Jim

 

[black85vette]

Very nice version of a rotary valve. I also did Elmer's rotary valve just because it was interesting to me. I like the scale of yours. Good job. Thm:

I assume the G clamp is the same as what we call the C clamp over here? Another bit of difference in our "common" language. :big:

 

[modeng2000]

Well done Paul, you must be pleased. ;D

I am part way through machining the 8 cast wheels for my loco. Cast iron is not the cleanest of metals to machine!

John