Something to try for a loose spline drive is make a fixture to hold the splined shaft and sleeve concentric so there's an even gap all around between the two and sealed at the bottom end so nothing can leak out.
The bore should be degreased and roughened by bead or sand blasting. The splined shaft will need to be uniformly straight and smooth, then have mold release applied, missing nowhere. I'd apply a couple of coats of TR-104 High Temp Mold release wax then spray on the release for whatever resin will be used to fill the gap. Injecting Moglice into the gap should work the best. That stuff is extremely hard and really bonds to iron and steel. I've used it to repair worn half nuts on metal lathes by clamping them to the far right end of the leadscrew to mold the resin to shape. How hard is it? It took quite a bit of effort to grind off the excess squeezed out Moglice with a grindstone in a Dremel. Epoxy or hard urethane with some graphite or PTFE powder mixed in might work too. Smooth-On has a bonding agent they call Ure-Bond that makes their resins and rubbers stick very well to metals. Might need a press to pop the shaft free, but the result should be a nearly zero clearance sliding fit that's not going to rattle. If the mold release does its job right, a soft face mallet ought to pop it loose. Another possibility would be DIY broaching a splined sleeve that's a much better fit, boring the pulley out to press the sleeve in, then touching up the splines if the sleeve compressed enough to make it too tight a fit. If Delrin or Acetal can be melted and injected in, that could make a zero clearance lining. It would need to be able to flow out on both ends to form a flange to keep it from sliding out of the bore. If it's a really large gap, make a brass or bronze sleeve to fit the splines on the shaft and pulley. Or perhaps just some strips laid into the grooves on the shaft, the pulley slid on, then the ends of the strips bent over and soldered to washers would take up the slack. _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
