I had a lumpy idler on my Garrard Lab 80 so I threw on a different one that I had trued and cleaned with CaiKleen RBR. The thing slipped so much it almost would not drive the platter at all: slow start up and slow final speed. Tried cleaning and recleaning and minor roughing with 320 emery cloth - negligible difference. I took some solid rock rosin and smashed it between two aluminum plates until it was as fine as talcum powder, rolled the idler's edge in the powder and brushed off the excess. The result was instant startup to perfect speed, and great resistance to slowing from finger drag on platter edge. Dramatic, instant and complete cure. No idea about whether this might help belt drives, too, or about long term issues, but for now, it's incredible. YMMV
Congratulations 2spit10 you have reinvented a product that I used while maintaining machine tools driven by a communal shaft multi pulley belt drive from a single massive electric motor , in other words very old school (Victorian ) engineering practices .
The firm was so mean it took them decades to introduce individual motor driven machine tools.
The firm was so mean it took them decades to introduce individual motor driven machine tools.
There was a time. I've used it on tape deck belts for better grip.
It helps also on finger oil contamination.