compressor for cox radial

I do hope you will succeed. There are a couple of engineers on RC Groups who swear a vane type compressor will not work at this size. I think it will. Check out the RCG engines forum for details, since as a newbie I can't post a link.

The other Geoff

If you're talking about iamplanecrazy's thread, it's turned into a real mudfight over that subject.

http://www.rcgroups.com/forums/showthread.php?t=1362796

The last few pages are getting tense.

It's only heated because of one tool posting in that thread. I have him blocked so his posts don't show up on RCG. I believe he was banned on RCU for doing the same thing over there. It gets old fast.

Jason

Are there springs loading the vanes or is it just centripetal forces keeping it sealed and outside?

Phil

Every vane pump I have worked on they are pushed out by centrifugal force. The only spring loaded device I have encountered in an engine are apex seals in the OS Wankel engine.

I had suggested to iamplanecrazy that he consider the very light carbon rotor and vanes from a forced air kerosene heater. He's built his radial with only a drill press and a good imagination, so is severely lacking in machinery! The nay-sayers jumped all over me, swearing that friction losses would exceed output with my suggested vane & rotor.

Jason, does your avatar show a rear rotor Olympic? Do you have a disassembled photo somewhere?

Geoff Mk II

This compressor has spring loaded vanes to insure constant contact with case. I tested compressors without springs and sometimes vanes failed to slide out properly, I think due to fuel causing sticking and the light weight of the vanes. Also tolerances have to be close to make a good seal. This is one proto type. Other options would be a larger diameter compressor or a longer compressor for more volume. The goal is to make the engine look realistic in size as well as run properly. I also have in mind a 6 cylinder radial with 3 cylinders running the engine and 3 pumping fuel under pressure. I am also about half way finished with a cox outboard motor. I hope to post pictures in near future.