I've just had the pulley wheel bearing on one of my 3060s wear out. (Yes, I have used it a lot.) It's a plain aluminium pulley wheel (not toothed) which tensions the 10mm drive belt. It's got flanges on either side to stop the belt skipping off, so the total width is 13mm. It sits on a 5mm spindle, retained by two standard "E" circlips. Trouble is, once the bearing gets worn enough, the pulley wheel stops sitting square, throws the belt, and... urk!!
Right now I'm intending to fabricate a temporary pulley wheel (maybe out of perspex?) so I can crack on with both lasers while I wait for a spare to arrive.
Got any suggestions for alternatives or better ideas?