I have questions about the engine mounts.I bought p/n 22387 from Aircraft Spruce.I was hoping that some of the seasoned veterans can comment on the following:
- These mounts don't meet Steve Kiblinger’s criteria of being able to close the hole with thumb pressure.They are closer to being hard as a rock.However, I’m guessing this is what people are using, because that’s all I could find.
- The cone angle isn’t 90 degrees, in fact it’s slightly less than 80.This being the case, if I use 45 degree angles on my mount tubes and spacers, I won’t get good contact with the angled face on the tube until the mount is significantly deformed.I can’t imagine this is what’s intended.
- The Joe Engleman engine mount stud must be for a mount other than the 22387.Anyone know which one?
I know I tend to over-analyze, but any comments on the above would be appreciated.Thanks.
Thanks for the information. I got my mount bushings from Aircraft Spruce. I just measured them, and they are 68 durometer, exactly to the spec's on the Sky Geek website. I looked in Mcmaster, but they don't have anything that looks like that. I looked in other places too. The only thing remotely similar is shock absorber bushings, but there aren't any durometer values listed. I'm going to have to go ahead with what I got since I've already fabricated station 1.
Steve, thanks for those ideas. I hadn't thought of bottle stoppers, although I have dabbled in machining 40 durometer urethane barstock from Mcmaster. It's like trying to machine a rubber band, and I have been moving toward one of the solutions (cutter rake and relief) mentioned in the link you provided, although there are a lot of ideas in there yet to try.