"Schertz, William W." wrote:

Paul,
You recommended McMaster Neoprene Isolated rod ends 6088K15 for the strut
from engine to firewall.  The 1/2" version of these has a radial load limit
of only 270 pounds, and no indicated thrust capability. They also can only
tolerate 3 degrees misalignment. Temperature range 32F to 180F.

Part Number 59915K26 is a stainless steel rod end with 4700 # radial load
and can have 17 degree misalignment (not that you need that much).

Part Number 8405k13 is 3/8 - 24 and has a load rating of 4854 in radial, and
1765 in thrust. Temp range -40F to 176F.  This seems stronger than the
neoprene isolated ones.

Do you think 270# is sufficient? And what happens if the end fails?

Bill Schertz
KIS Cruiser #4045

I agree a stainless ball joint is much stronger.

It's for the rear motor mount. Static load is less than 50 pounds with 
a six G load three hundred pounds. Should be OK. I think that 270 pound rating is for
continuos load. Angular should never get to 3 degrees if its installed
straight to begin with. I think the 1/2 size is very conservative. 

If the rubber fails the steel part will capture the bolt if large safety washers
are used.  Recommended with any aircraft ball joint.

The Barry main mounts are about 200 pounds static but then the 6G load is
900 pounds each.

I like the potential reduction in vibration over a solid steel joint.

Paul Lamar


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