valve seating

[daddio]

I am building 5 forest Edwards 5 cylinder radial engines. I am almost complete but I am having trouble with compression. My rings seem to be holding compression but the valves are not. I am in the process of designing a press in valve seat out of 954 bronze. I am also planning on putting in a viton seal behind the seal plug. My valve guides are machined into the head it self. Any input?
PS I am new to this site so bear with me.

 

[petertha]

Hi daddio & welcome. If you type 'valve seal' into the search box on this same Q&A sub-forum, you will get quite a few hits. Here is one I started & I believe I referenced some other links within the post.
http://www.homemodelenginemachinist.com/showthread.php?t=24516

Another suggestion is to do a search under 'Edwards' & you will likely see some build posts & description/pics of how those particular individuals accomplished that step. (Maybe back up to Building Them sub-forum vs. Q&A)

I'm (slowly!) building a radial myself so would love to see some of your Edwards build pics one day.

 

[gbritnell]

I would suggest making a valve seat cutting tool and cutting the seats once they are put in place otherwise the seat and guide might not be concentric. I had posted a drawing for the cutter some time back but I'm not at home presently to search for it.
gbritnell

 

[daddio]

Here is a picture of one of my engines. I had originally planned on producing them in quantity. I have a small
cnc machine shop. They are a lot of work, and I don't think I can sell them for enough to profit. I am planning
on mounting one to an airplane, but first I have to get them running.

 

[petertha]

Nice looking engine!

Conversation #7 of this post has George's seat cutter drawing. (I think he discussed it more detail in another post, but cant locate that right now)
http://www.homemodelenginemachinist.com/showthread.php?t=26022&highlight=valve+seal