On Wednesday 10 March 2021 12:58:08 John Dammeyer wrote: > Hi Sam, > I found by making the wall thickness bigger along with the hole > smaller and hub larger I was able to mount the hub on the lathe and > bore both the bore and the outer part of the hub on the lathe to make > them symmetrical. That reduced a lot of wobble compared to earlier > versions. > > In hindsight I would also have made some sort of holder that allowed > me to skim the inside of the actually pulley part. Instead I used > sandpaper because as you can see it has the same roughness from the 3D > printer as your toothed belt section has. > > The hub was a smooth press fit (by hand) in and out of the pulley > part. The photo showing it mounted still has the yellow pulley that > had too small of a hub and the pressure from the set screw cracked it. > So the new green one has a wider set screw area. > > I suspect the biggest issue with your flex pulley would be holding it > stable enough so you could skim away material. Might even be best to > print it with a flat face to hold it round. Then mount it in a > holder, skim the inside surface and then cut through the face at the > back. The flat face could even have mounting holes to mount onto the > back of your plate. This would keep it from turning in the mount > while you skim it. > > John > Hi you two;
I've manage to beat openscad into enough submission to make the loose belt, approx 99mm at pitch diameter. With 60 "teeth" which are actually from equalateral triangles. Now I've turned the triangles 180 degree so they face inward and increased the pitch radius to 54.5, and now making a 62 tooth outer ring for fit testing. But it occurs to me since I need a lessor gear ratio than 30/1, that I might be able to cheat a bit on the output ring, and get half the gear ratio and twice the speed if I made the the output ring with 58 teeth. I'm obviusly way behind you two, but before I waste a $30 roll of PETG, I thought I'd throw it out there for target practice by more experienced people. Discuss? Tell me I'm out of my mind, your choice. :) > > From: Sam Sokolik [mailto:[email protected]] > > > > another update - at 1/2 step - the discrete resolution should be > > about 40,000 divisions per rotation. .009 deg. > > > > https://www.youtube.com/watch?v=IdfKre6zpEY > > > > On Thu, Feb 4, 2021 at 4:00 PM Sam Sokolik <[email protected]> wrote: > > > https://www.youtube.com/watch?v=ZVVffljc7kE Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
