The screw that tightens the adjustable mouthpiece receiver on my Adam's E1 recently snapped in two as I was tightening it -- maybe I was going too tight, I don't know. As an instrument many years old, I assume something small in diameter can eventually fail due to the stress of tightening/loosening over time. I was able to have the piece of screw removed and I have a factory replacement screw. My question is what is the most appropriate lubricant for the screw threads? I assume it would not be a grease, but instead should be an oil. Valve oil? A penetrating oil? Something like 3 in 1 oil? Any recommendations?