On Wednesday 27 April 2016 04:34:33 Gregg Eshelman wrote: > Center distance of the shafts for the motor and leadscrew on my lathe > are just a bit over 77mm. Motor shaft is 3/8". Screw shaft is 10mm. > (Yup, surplus parts, ya gets what there is.) I want to do a 2:1 > reduction, which with 1/2 stepping the 200 step motor will get 0.02 mm > move per step from the 16 mm per turn ball screw. It's a 9x20 lathe > and the motor is a Slo-Syn brand, label says 450oz holding torque. > Specs on the motor say 5% accuracy so I wouldn't expect 1/16th > stepping to consistently produce 0.01 mm movement with a 2:1 > reduction. > > There's very little adjustment on the motor mount so I'll likely need > to use a smooth idler against the back of the belt. There is room > where I could put an idler on the inside of the belt and use some > arbitrary length, but shorter belt = stiffer and better accuracy, > right? > > Recommendations on pulleys, tooth profile and belt length / number of > teeth? I have lathes so I can ream a 3/8" out to 10mm.
Not a recommendation Gregg, but I didn't use a belt for Z drive on my 7x12. I'd bought a full set of metal change gears for it and since I wasn't using them anymore, I made miniature taper-lock hubs for two of them. 1/4" bore on the 425 motor into a 40 tooth gear, and a 10mm for the stub of the 16x5mm Z screw I used was fitted into one of the 80 teeth gears for a 2/1 reduction. But my 2m542 driver is set for a /8 microstep as that got me a huge reduction in gear rattling when combined with a damper on the other end of the motor. With about 37 volts for the motors, my rapids on the Z are set for 60 IPM limit which is a bit of overkill for a 7x12, but its bulletproof. And if I run it into the tailstock it just shoves it on down the bed even if its tightened well for drilling a big hole. 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> ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
