Silicon O rings

[spurley]

Hi All

Since asking the question about Tich piston rings, I have bought suitable sized silicon rings (112s) from
Macclesfield Model Engineer's Supplies. I machined the grooves to the sizes specified in Tubal Cain's handbook. The compression is quite impressive now but my fear is that the finish may not be smooth enough. I am sure time will tell? I also bought suitably sized rings for packing the glands, I will eventually complete this machine and can then tell anyone, still alive , how they stand up.

For info Viton O rings are also available in Macclesfield.

Cheers

Brian

[the_viffer]

A well known professional model engineer told me that you should expect the first set of O rings to wear out quickly. This removes the 'umps and 'ollers from the bore and the second and later sets last much longer.


Silicon by the way is what computer chips are made of. Silicone is what O rings and page 3 models are made of.

[spurley]

Your quit right about my splling!!! I think I have the keyboard from the Two Ronnie's famous 'Quoon' sketch!!

I'll advise on the wear once the engine is finished. I did by spares so they can be changed fairly easily if necessary.

Cheers

Brian

[Phil Sutton]

Hi Brian,did you hone out the bores when you finished machining them?You really need a smooth surface or the O rings will wear out as fast as you can relace them.
I know you can buy small diameter hones from Blackgates,Reeves etc,but be careful not to bell mouth the cylinder ends.

Phil