The fact that you mention that the tick only recurs after some lapse of time suggests to me that it is some kind of contamination of the knuckles (I'm assuming its a grand because of your description of the symptom--this could just be another visualization gone awry!). I have seen this from lacquer based lubricants being used on knuckles, my partner Jack has just such a specimen. The lacquer pools on the bottom/ outside of the skin and the jack or maybe even just the window must break free of the bond that forms after a couple of hours, causing the tick. I would be suprised if any surface treatment had a lasting effect. Other techs have indicated to me over the years that basically you have to replace knuckles once they have been lacqued if you want to get rid of the symptom. You can try brushing them (hard with a brass wire brush) (then applying teflon powder) but as they compress the tick may return. Of course, this could be an opportunity to replace the shanks as well if you have teflon bushings involved. Best wishes, Audrey Karabinus, Seattle
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