Hi Rick, This is a question that is asked all the time on the E-Leadscrew group.
I have a South Bend Heavy 10L with a taper attachment so I haven't yet gotten around to powering the X axis. I have a 280 oz-in stepper through a 2:1 belt drive on the Z in order to be able to cut metric threads using the ELS. Part of the reason is, I don't care as much about really fast traverse speed and with the back gear, the 2:1 stepper (about 300 RPM lead screw speed) can keep up with any threading speed I might throw at it. That way I could use the on board 3A 48V stepper driver included in the ELS kit. On similar sized lathes others have gone to direct drive with size 34 motors that have a torque between 500oz-in and 900 oz-in. Although expensive compared to far east imports the GECKO driver is good to 8A I believe and 80V and work on either size motor. Start with a 500 oz motor and if you find the torque too low move it to the cross slide and buy a 900 oz for the carriage. What I always suggest for people who are trying to augment a lathe that has missing gears is start with an ELS and just the Z axis. If it turns out the motor is a bit small you can always use it on the cross slide since that doesn't take as much power. Then upsize to a size 34 and a GECKO for the carriage. What I did with my South Bend was to create a shaft adaptor onto which I milled HEX flats to take a 1" socket. I tried measuring with my torque wrench how much torque it would take to twist the lead screw while cutting steel. That was a useless endeavor since it didn't even move the needle. So back to basics with a flex handle on the 1" socket and 1' away I started adding weight. Each oz would be 12 oz-in. As I recall it took very little to move it. Perhaps 50 oz-in. I looked at the torque curve for the 280 oz-in motor and at about 750 rpm with the 2:1 belt drive I was still in the motor spec for motion so that's the way I went. BTW. I used the same process with my Knee on my mill and found a 500 oz-in size 34 would work with 3:1 so I initially drove it with the ELS 3A drive and series connected motor. It did work but the speed was painfully slow before it lost steps and locked up. However that happened at the exact point in the torque curve of the motor connected and driven as it was. Final solution there was a GECKO, and 900 oz-in parallel connected winding drawing 6A and 48V. For a 9" lathe you can use a 3A size 23 stepper and 2:1 reduction drive at the expense of rapid speed. John Dammeyer "ELS! Nothing else works as well for your Lathe" Automation Artisans Inc. http://www.autoartisans.com/ELS/ Ph. 1 250 544 4950 > -----Original Message----- > From: Rick Lair [mailto:[email protected]] > Sent: January-13-16 8:10 AM > To: Emc Users > Subject: [Emc-users] Stepper Motors/Drives > > > Hey Guys, > > I have never dealt with stepper motors/drives and one of the guys at our > shop is kicking around converting and old 9x30 Southbend lathe to cnc > using Linuxcnc. Are there any recommendations on maybe some kits with > all the power stuff (motors, power supplies, cables, etc,) that anybody > recommends. I am up in the air on the control hardware, but I can handle > that, I just don't know where to start on sizing/selecting the stepper > stuff. > > > -- > > Thanks > > > Rick Lair > Superior Roll & Turning LLC > 399 East Center Street > Petersburg MI, 49270 > PH: 734-279-1831 > FAX: 734-279-1166 > www.superiorroll.com > > > ---------------------------------------------------------------------------- -- > Site24x7 APM Insight: Get Deep Visibility into Application Performance > APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month > Monitor end-to-end web transactions and take corrective actions now > Troubleshoot faster and improve end-user experience. Signup Now! > http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140 > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
