Play in motor shaft

[GlenP]

Has anyone with a newer PRS standard had or noticed any play in the motor shafts. I have had some cut issues and chattering noise which I thought maybe was loose pinion gears. I checked the gears and they are tight. I can however wiggle the gear back and forth as well as a bit of end play. I pulled all the gears and three out of the four do this and the forth on is tight at one spot, spin the gear and it get loose as well. I have read about backlash tolerence but don't have any way to meassure how much play there is. Shopbot wants me send them back to them to check them out but wondered if anyone has had anything simular or can shed some light on motor play.

[Brady Watson]

Glen,
ALL gearbox motors have some end play and backlash to them. Normally, you should not be able to feel either, especially since SB uses low backlash spec motors. It's probably best that you send them back. I use other Vexta gearbox motors on machines that sometimes run for days at a time & after a while, they get a little louder than they were when new. That's to be expected...but your situation sounds out of the ordinary. Let us know how you make out.

-B

[GlenP]

thanks brady, frank wants me to ship them back tomorrow. He is puzzled because they don't have alot of motor problems. I hope they get them back to me quick, going to be down for awhile. I do have to say that once again shopbot support is aces. Frank returned my call and spent alot of time on the phone to help isolate and then immediately gave me a return for the motors. Most companies would give you the old "your not our only customer" excuse and call you next week.

[richards]

Stepper motors have Axial play (shaft moving in and out). Geared motors might have a little Radial play (clockwise and counter-clockwise shaft rotation).

When powered up, an Oriental Motor geared stepper motor might have only a very minor amount of radial play. Axial play should not affect the accuracy of the cut, but radial play, becomes backlash when the motor reverses directions.