Peter Cowan wrote:

Can anyone give me suggestions on this spring gear attach problem?
What I've got is a Cessna 185 spring gear on a steel tube airframe. The "U" bolt is a 3/4 x 1"
aluminum bar with two 3/8 bolts. Here is a picture looking out from the center of the fuselage to
the right gear leg. The frame would be at the top; the gear in the notch:


The last couple of flights I noticed oscillation at the wheel just after first touch down
indicating the gear was loose. Lifting the plane off the ground allowed the gear to really flop
around. You can see that the bar is bent on the left (to front of the plane). The odd shaped
blocks were cut to position the gear with the correct toe in/out and clear structural tube. Unlike
Cessna installations these retaining bolts are a couple of inches further away from the gear on
each side.
I can replace this assembly with one made up out of steel but would like to build in some "give".
Is there any rubber type material that could with stand the loads yet provide some cushioning in
this area? One thought was to wrap the gear in multiple layers of a glass cloth and silicon
laminate. Any other suggestions are appreciated.
Peter

Fiberglass reinforced rubber belt material would work fine. No way around the bending
problem other than steel unless that aluminum is a soft alloy. Try making it out of
7075 T6. Also make it 1" by 1" instead of 3/4 by 1. That way it will be only
25% heavier instead of three times heavier.  

Paul Lamar
 
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