On Tuesday 20 September 2016 14:29:57 Chris Albertson wrote: > I'm surprised you can cut XL pulleys with a hob. It does not look > like the teeth are right for that to work. If I had to make an XL > pulley from scratch, I'd guess the best way would be to use a 4-axis > machine and a ball-end mill. That is one reason I'm wanting to add a > motor to my rotary table. I have a number of small wheels and the > like I want to make. > The ball end wouldn't be the tool for the job as the bottom of the gullet has sharp corners except for the OEM belt of a 7x12. And there are 2 common face angles in use and I've not the memory to quote whether its 14.5 degrees or 20 degrees for the face angle per belt tooth style.
Bigger than xl is probaqbly 20 degrees but that leads to belt hopping if not tighter than a drum so I'd assume its 14.5 on the xl as they will rip the teeth off the backing before they'll hop a tooth, assuming the shaft centers can't flex. That was one of the original problems with TLM, and once it had hopped, it just sat there burning up both the belt and the OEM plastic pulley. But I have that braced against a jack screw now, and all metal pulleys and gears in the headstock. So I can now put 30x the torque into the spindle compared to the OEM kludge. Just this past week, I had drive enough to take .4 mm's per pass off a 4.5" diameter piece of large car wheel casting iron. OEM drive, I had to sneak up on a piece of 3/4" cold roll in the chuck otherwise it couldn't pull it, stalling the OEM 400 watt motor. > On Tue, Sep 20, 2016 at 10:53 AM, Andy Pugh <bodge...@gmail.com> wrote: > > On 20 Sep 2016, at 03:00, Gene Heskett <ghesk...@shentel.net> wrote: > > >> I have the hob to make T5 pulleys. > > > > > > Yeah, but my GMC doesn't have pontoons and paddlewheels. ;-) > > > > You could send a drawing, but I think that my turnaround time would > > be a problem as I am in Turkey until the weekend and probably > > wouldn't get started until the weekend after. > > > > > > ------------------------------------------------------------ > > ------------------ > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users 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) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
