RCU Forums - View Single Post - Contra Rotating Propeller Drive for f3a 2m Pattern Planes
Old 05-01-2016, 08:51 AM
  #1634  
Brenner
 
Join Date: Jul 2007
Location: Bridgman, MI
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Mike Gaishin has been trying a new set of vibration grommets from EAR Specialty Composites.

These grommets are specifically designed to minimize vibration amplitude at resonance, and isolate it above resonance. The damping factor of the material they use is formulated specifically for this purpose.

These are what Mike is using. They are a drop-in replacement for the Budd Engineering grommets. Mike is still using the nylon bushing, the bolt, the carbon fiber plates, and the carbon fiber washers that we ship with each Drive.



I have just installed a set on my plane, and so far I am very impressed. Any resonance that exists when I spin my Drive up is very hard to notice, if at all, and the isolation at max throttle is excellent.

They are available molded with several materials, but the ones I have are made with C-1002 material which is blue.

Right now I don't know how durable or reliable they will be, but I am going to be testing them in the coming weeks, so I hope to find out.

Regardless though, if anyone want to try them, they can be purchased from McMaster-Carr. The part numbers are: 9311K145, & 9311K143.

Brenner ...
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Last edited by Brenner; 05-14-2016 at 10:45 AM. Reason: Part Number was wrong ...