Lyman 48C

J

JRLesan@embarqm

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The serrated windage adjustment knob on my 48 C is lightly(.001) loose on the windage adjustment spindle. It was designed with a setscrew to retain it and shows no signs whatsoever of spinning on the spindle shaft, but is loose. Tightening the set screw (into the recess in the spindle shaft) throws the knob slight out of true with the shaft causing the knob to wobble slightly. Is there a loctite product (or other product) that could be applied to the shaft to create a slight interference fit yet still allow the knob to be removed? The elevation knob is secured to its shaft in the same manner and with the set (retaining) screw removed is a tight interference fit. I did not remove that knob as it was unnecessary. The wobble in the elevation knob causes the detent spring (which indicates clicks of adjustment) to skip if one is not paying attention. Thanks...
 
I know it

JRLesan@embarqm said:
The serrated windage adjustment knob on my 48 C is lightly(.001) loose on the windage adjustment spindle. It was designed with a setscrew to retain it and shows no signs whatsoever of spinning on the spindle shaft, but is loose. Tightening the set screw (into the recess in the spindle shaft) throws the knob slight out of true with the shaft causing the knob to wobble slightly. Is there a loctite product (or other product) that could be applied to the shaft to create a slight interference fit yet still allow the knob to be removed? The elevation knob is secured to its shaft in the same manner and with the set (retaining) screw removed is a tight interference fit. I did not remove that knob as it was unnecessary. The wobble in the elevation knob causes the detent spring (which indicates clicks of adjustment) to skip if one is not paying attention. Thanks...
Click to expand...

sounds spooky. but I would bed the knob to the spindle. Silicone the living hell out of the spindle and then clean the bejesus out of the inside of the knob. I would use a SMALL blob of JB at the top of the knob cavity and let it squish around the end of the shaft. Set it aside for 24 hours and you should be good to go.
 
JRLesan@embarqm said:
The serrated windage adjustment knob on my 48 C is lightly(.001) loose on the windage adjustment spindle. It was designed with a setscrew to retain it and shows no signs whatsoever of spinning on the spindle shaft, but is loose. Tightening the set screw (into the recess in the spindle shaft) throws the knob slight out of true with the shaft causing the knob to wobble slightly. Is there a loctite product (or other product) that could be applied to the shaft to create a slight interference fit yet still allow the knob to be removed? The elevation knob is secured to its shaft in the same manner and with the set (retaining) screw removed is a tight interference fit. I did not remove that knob as it was unnecessary. The wobble in the elevation knob causes the detent spring (which indicates clicks of adjustment) to skip if one is not paying attention. Thanks...
Click to expand...

I would send it to Bill Ackerman.
 
Pete, go

Pete Wass said:
I would send it to Bill Ackerman.
Click to expand...

back and read the original post. Doubt if this anything that Bill will do. He has either a oversize knob or a undersize shaft. The JB route is pretty much it to maintain an even spin. Bill (or his daughter) will do a lot, but i doubt this one. They basically work on the internals, not externals. God knows I have sent him/them enough scopes over the years.

David
 
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No responses early on so I used loctite 680 on shaft and knob, holding the click spring compressed and the setscrew hole in knob aligned with detent in shaft. Put wax paper between between back of shaft and click spring. I let everything cure for 6 hours, cleaned off excess loctite on face of knob between shaft and knob with a razorblade (where it had crept out), seated set screw (a 2-56 slotted) and knob runs true to shaft with 8 clicks per revolution. It took a number of revolutions of shaft to get the final remnants of wax paper out from under the knob. Chances are it will never get turned again in my lifetime after I get it sighted in.Thanks...
 
Glad

JRLesan@embarqm said:
No responses early on so I used loctite 680 on shaft and knob, holding the click spring compressed and the setscrew hole in knob aligned with detent in shaft. Put wax paper between between back of shaft and click spring. I let everything cure for 6 hours, cleaned off excess loctite on face of knob between shaft and knob with a razorblade (where it had crept out), seated set screw (a 2-56 slotted) and knob runs true to shaft with 8 clicks per revolution. It took a number of revolutions of shaft to get the final remnants of wax paper out from under the knob. Chances are it will never get turned again in my lifetime after I get it sighted in.Thanks...
Click to expand...

it worked. Same effect, different method. Good job
 
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