REFLECTOR: Brake shudder - RG

[Al Gietzen]

After the first few landings with the Matco brakes, I began to get 'shudder'
of the main gear somewhere in the 40 - 30 kt range when applying the brakes
on roll out.  This can be annoying, as well as cause a pretty good shake of
the plane.  I'm told this is common with Velocitys.  There is a point of
resonance involved here, and there must be a driving force.  

 

I recall someone posted here about just a few mils distortion of the rotors
causing this, and milling the rotors true solved the problem.  Do I recall
correctly, and did the problem stay solved?  Where/how did you get them
trued up?

 

While investigating the issue, I found that the retracted position now the
gear is about 1/8 - 3/16" further forward in the wells, which eliminated the
clearance of the gear doors to the stake opening.  Is this a common
occurrence?  I thought that perhaps the pivot bolts on my 1996 kit were not
grade 8 and may be bent a bit, but they were grade 8.  I changed them out
anyway, and found it eliminated a bit of play.  Examining the bolts shows
that they were not very round, and the high spots were worn.  I think the
new bolts are more true.

 

I also noted there was now about .010 - .015" fore-aft movement of the gear
(the spacers originally fit very close), and the bolts were loosely
tightened to allow them to rotate in the bushings, rather than the sleeve in
the leg rotating on the bolts.  When I installed the new bolts I tightened
them a bit more which reduced the clearance, but will mean that the bolts
will not rotate in the bushings.  Any opinion on whether it matters?

 

Thanks,

 

Al

 

 

Thanks,

 

All

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.tvbf.org/mailman/private/reflector/attachments/20061203/371aef05/attachment.htm