Scratchy slide

Hi. My slide head always has slid (slided,slood?) smoothly, but now it feels kind of scratchy and almost tight in there. I have cleaned both the inside and outside with paper towels and applied more grease, but alas, it isn’t helping. I have been using cork grease, but an instrument repair guy told me to use vasoline, b/c it is so much cheaper. It seems to work fine on the corks. Have any of you ever encountered a problem like this? Part of the problem could be the heat wave we are experiencing in New England. It is over 90 degrees here and has been for a while. So maybe the heat is causing the grease to melt and not lubricate the slide? i don’t know. Or maybe there is a better grease to use on slides. Any input would be very helpful. Thank you.

Try lanolin - it’s cheap, too, and it doesn’t melt away as fast as vaseline…

Pat