I bought an 8mm lead screw on amazon and found out the openbuilds lead screws are actually 7.8mm in diameter not 8.0mm. Anyway, the openbuilds part store is out of the 500mm length. Can someone tell me if there is another source for these? I was bummed that the 8mm lead screw that I bought wouldn't fit in the bearings or the openbuilds flexible coupling. I'm sure they could be pressed on but that would be a pain... -Eric
Hello Eric, You could sand the ends of the screw to get it just under 8mm and fit them in the coupling and bearings. -Ronald
The anti backlash nut loosens up with use. The Openbuilds parts store used to sell the true 8mm screws and there were enough complaints that now Mark has them specially rolled for a better fit. But yes, the recommendation at the time was to lightly sand the ends and to chuck the screw in a drill and run the nut-blocks up and down a few times to loosen them up.
My brand new CBeam machine build seems rather noisy and I've noticed the bearings are rather loose on the lead screws. Any suggestions on how to tighten them up, or thoughts on the loose fit of the bearings causing noisy actuation.. Any suggestions how to track down the cause of the noisy actuation
Others and myself have used Teflon tape (the stuff used for sealing thread joints) wrapped around the acme, between the acme and bearing to remove the loose fit and to make it a little less noisy. Some thin copper / brass shim material would possibly be more durable. Inside dia of bearing minus the outside dia of the acme divided by two should get you into the ballpark for thickness of shim material needed. Hope that helps.
Both of those seem to be great ideas... I'll give that a try. Thanks a ton. Students were so hyped up about building the machine and impressed when it finally started to move! But they were disappointed in the noise... Great experience though cause it gives them a chance to troubleshoot and move forward with! Thanks again!
