On 8/6/2015 11:34 AM, Gene Heskett wrote: > On Thursday 06 August 2015 11:14:15 Dave Cole wrote: > >> On 8/6/2015 10:12 AM, Gene Heskett wrote: >>> Question, since the motors can get quite warm, how do you fix a >>> die-cast 1x1x2.5" box to a motor? Most modern glues tend to come >>> apart at higher temps. >> I've used Epoxy to glue die cast boxes to Stepper motors with great >> success. Drill a hole in the back of the box to cover the hole in the >> motor where the leads exit and glue it on. >> I think I roughed up the surface of the box and the motor with a >> sanding disk. > Not the motors laminations I hope. That, with a sanding disk could lead > to smearing of the metal and inter-lamination shorts and could cause > some localized very high heating. Gently hand sanding with a 320 sponge > to remove _some_ of the paint might be tolerable though. > >> I think I used Devcon brand but I think that JB Weld >> would work as well. The JB Weld has a filler in it that might help >> bridge some gaps. 3M has some interesting epoxy called Scotch Weld >> that also looks promising. >> >> Dave > Devcon is the "Bondo" maker. Lots of "void" filler in that. What I have > on hand is several years old, leftover from repairing the bottom of my > boat. And probably needs to go out with the trash. But JB Weld sounds > like a better idea. I'll see if I can locate some as there's none in > the toolbox ATM. I don't recall ever seeing the Scotch product locally, > but haven't looked for it either. > > Thanks Dave. > > Cheers, Gene Heskett
Yep, laminations and all. Didn't affect the motors at all. I didn't grind them hard, just enough to take the paint off with the abrasive disk so the epoxy would have a good bite on the steel. That was 3+ years ago and the machine is still going strong. Non of the boxes have came off. I tried to twist one box off after the epoxy set but it was firmly adhered. Epoxy is handy stuff. The Devcon I used didn't have any filler in it at all. (I have filler I could have added, as I do fiberglass boat work, but it was not needed.) I also waterproofed the motors via an epoxy coating over the entire motor (12 of them) so they could operate outside in the weather and I installed shaft seals. They were then painted over the epoxy as well to protect the epoxy from UV rays. A chinese company was basically doing the same thing, but they couldn't deliver the motors for 16+ weeks so I had to do the modifications myself to standard, off the shelf, Nema 34 motors. The motors were oversized for the application and run at reduced current. I would have rather not had to use the boxes, but we needed a junction box on the motor so we could junction a flexible cable at the motor with a waterproof cord grip. Dave --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
