If you are going to clamp a metal disc with anything, use an electromagnet... But if it's a worm drive with that much slop, I guarantee there's some improvement to be found by controlling the thrust movement of the pinion gear. Inserting a shim (could be punched out of an old set of feeler guages) under the gear where it shoulders up to the case can probably reduce the backlash by a significant amount.
*Ryan McIntosh* E4F Designs (204)770-3682 r...@pebkac.ca On Thu, Nov 23, 2023 at 1:25 PM Chris Albertson <albertson.ch...@gmail.com> wrote: > > > > On Nov 22, 2023, at 1:06 PM, gene heskett <ghesk...@shentel.net> wrote: > >> > > I'd have to agree Andy. I need to design a disk brake for my A axis as > there's half a degree of slop in the worm drive which if it gets to the > motor will be held, but the slop in the worm makes for sloppy looking > holes, but the activation method is still in my head. Even that is only > important when drilling a hole for the handle. I'll come up with something. > > Would a simple disk brake work? I think it might clamp the part any place > within that 1/2 degree of slop range. Ideally, you would have an index > plate and some way to place a pin in a hole to lock the table. But you > could only have a few holes and not enough holes for one at every place you > might want to stop. > > What if the disk had “V” slots cut in the edge. Like a very large US > Quarter Dollar, but with maybe 360 grooves. Then you could wedge a shape > (like a tiny axe head?) into the slot and force the disk to stop on an even > degree. You could use more than one wedge, space them around the disk. > > A wedge would need a lot less clamp force than a brake disk pad because it > is a mechanical lock almost like an index pin > > If you still want a “disk brake” why not use an actual disk brake from a > bicycle? They are about the right size, have huge holding power, and don’t > cost all that much. The ones you would want to use are hydraulic so the > electric actuator could be a couple feet from the rotating table. They > still make cheaper ones that use cable but avoid those, they are too hard > to adjust. > > Or maybe both, Use the slot and wedge to aligh the table to the nearest > degree and then clamp it with a hydraulic disk brake. Cost is under $100. > > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
