[Test-Equipment] Tektronix T935A Scope - seized knobs

[RJ Mattson]

Found no binding on the knobs. I had to open the cabinet and look 
internally.
Followed VAR knob shafts to 1k pots on board - Found seizure to be in 1k pot 
bushings.
Sprayed bushings lightly with Chemtronics "Trol-Aid" from 1970's.
Worked in lube and they slowly loosened up enough to turn from front red VAR 
knobs with just fingertips.
Will re-assemble tomorrow - how much should I charge myself ?

Back to tube radios,

bob...w2ami x wn2ami 1962

----- Original Message ----- 
From: <cemilton at aol.com>
Subject: Re: [Test-Equipment] Tektronix T935A Scope - seized knobs

Could be the knobs have been pressed "inward" to the extent they are seizing 
on the mounting nut.
Try loosening and backing them out about 1/16".  Just another idea. ymmv
73 Chuck W4MIL

-----Original Message-----
Tektronix T935A Scope.
 The center red "VAR" knobs on both Chan A & B Volts/Div Amp. knobs have
 seized.  In other words, either red knob won't turn at all.  What is the
 cure?  Do I have to open the cabinet to work in a penetrating oil on the
 shafts from the inside?
 Or, Just remove the knobs and try to un- seize the shaft from the outside?
 Or ?