Thanks to the words of Steve Vestuti on this forum last week I believe =
we may have cured the nosewheel shimmy experienced on hard runways. The =
British agent for Nye Lubricants Inc, (www.newgatesimms.co.uk) was =
extremely helpful and sent two 50grm pots of damping grease for me to =
try. I decided to use the less thick of the two (NYE NYOGEL 767A) first =
and coated both the shaft and washer. Test flying in a quartering 15kts =
crosswind with high touchdown speed resulted in no shimmy, and best of =
all the braking required to turn had been reduced to light fingertip =
pressure and accuracy of control never before experienced. Lubricating =
the "friction" washer naturally make it impossible to achieve 8-9kgs of =
static friction before the nosewheel turned, but by cranking the shaft =
nut up more than before (Bob you are making me nervous now!!) I achieved =
a "snatch" value on the spring balance of 8 kg and 2kgs before the wheel =
started to move with a steady pull. I now intend experimenting with NYE =
PG44A grease which is the thickest grease in their range, in the hope =
that the shaft nut can be backed off some for the same friction figures.
My thanks to Steve for introducing me to damping grease, a subject I had =
never heard of previously. =20
and to Bob Harrison - sorry to hear about the lost nosewheel and =
consequent damage. Roll pins never did get my vote.
Brian Tarmar G-OBJT Classic Trigear XS Front 912S=20
75 hours and smile fast returning
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