Locking compound for teleconverter lens sub-assemblies?

[roydonian]

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I recently acquired an example of the X2 teleconverter that the late Mr Benatti created by modifying the commercially available Kenko teleconverters of the time.

 

I don't know if the unit I have was a prototype or a production example, but it has two freely-moving adjustments. If any form of locking compound was applied when the unit was built, it has long since lost its effects.

 

The optical group is in a threaded assembly that screws into a threaded hole in the centre of the unit. A little experimentation has shown that its position is very critical - quarter of a turn away from the optimum location has a significant effect on image sharpness.

 

The plunger that communicates the movement of the lens cam to the roller-equipped lever in the camera body incorporates a screw that the can be moved to adjust its exact length.

 

So the obvious way head will be to adjust the position of the optical so that the image of a distant electricity pylon is as sharp as possible when the lens mounted on the teleconverter is set to infinity.

That done, the screw that adjusts plunger length will have to be adjusted until the two images of the pylon coincide when the lens is set to infinity.

 

My question now is - what kind of locking compound should I apply to these threaded components so that the results of my adjustments becomes semi-permanent? My first thoughts are that I need a weaker and slower-setting equivalent of the Locktite liquid used to secure screws that will be subjected to vibration - something what allows parts to be moved freely for some hours after application, and with enough strength to hold the results of my adjustments, but weak enough to be loosened at some time in the future should this be necessary.

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[dkCambridgeshire]

Google 'slow cure thread locking compound' … Loctite 635 is one possibility … there are many different grades of Loctite. But Loctite is not the only brand.

 

dunk