On 01/24/2017 01:04 PM, Gene Heskett wrote: > On Tuesday 24 January 2017 09:49:12 Ed wrote: > >> >> RANT MODE ON >> >> Why in this day of cheap encoders, small ebay servo motors, and good >> inexpensive servo drives does any one even use stepper motors? >> >> Dampers, resonance issues, lost steps, stalls, only 30 IPM? Why? >> >> Gene, don't stay on the dark side! Go to servo's and don't look back, >> you will never regret it. >> >> RANT MODE OFF >> > Because the stepper motor at up to 470 oz/in can be had for under a $40 > bill, and a suitable driver for the mid $30's (nema 23), or mid $60's > for a nema 34 if you don't need 3k revs and a suitable psu for less than > $40 for either, less than $150 an axis worst case. Yes, and now you've proven they DON'T work, and you are having to come up with all sorts of Rube Goldberg hacks to try to make it work for you. > The only servo drive I am familiar with is $120, and motors with encoders > are around $250 and up to $2500 on ebay right now (and obviously too > long as I only have about 118 mm for the x motors depth) , and the > interfaces giving the analog voltages the servo driver's need are about > $20 an axis more? Although the vfd I find is happier that that famous > hog being fed by a pdm signal at a 10 khz pulse rate) Automation technologies Inc (formerly Kelinginc) has some VERY affordable brush and brushless motors. I've used their brushless motors with my servo amps and they work quite well. > So here's a challenge Ed, find me a 2 axis kit that can move this 11x36 > with as much torque at working speeds as these steppers can make, for a > $300 bill, Well, you can keep picking up items on eBay and trying to get lucky, but you may end up with a lot more of the same trouble.
Jon ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
