So I decided to follow in the footsteps of others and upgrade to linear rails and ball screws. Everything went great, had the gantry sliding front to back and side to side with no issues. Installed the ball screws and still no issues. Installed larger steppers, and that is where my problems began.
Snugged up all the screw on the motor and spun by hand to make sure there was no binding, there wasn’t. Turned on the S3XXL with homing off and both Y motors and the x started grinding when jogged. Went over everything several times, disassembled and re assembled 3x and now its disassembled.
So I only bolted the motors down with one screw, finger tight, and jogged it without the ball screw attached. The motor still made an awful grinding noise. Then with all the screws loosened about a 1/4 turn, I jogged it and it sounded great.
I’m at a loss now. A friend told me to ground the motors, didn’t help. A coworker told me to just not tighten the screws all the way… uh, no. Now I’m wondering if I got 3 bad steppers or am I over looking something?
Hopefully these videos work
Any ideas, thoughts or solutions would be greatly appreciated.
At first was going to suggest that you check all your wiring and make sure that all the motor phases are hooked up correctly but it seems like your motors spin correctly and then simply jam. Checked your motor’s spec sheet and you might have chosen wrong motors for your application. Nema23 that you picked up have incredibly high inductance - Inductance: 17mH+/-20%(1KHz)
You’ll want the motors with as low inductance as possible. I recently bought nema24 closed loop steppers with inductance lower than 2mH and they spin very fast and don’t jam at all.
You should do some reading on the “low vs high inductance stepper motors”. Also if you’re using your new setup with carbide 3d original board, the performance of your system will be, at most, satisfactory. Direct ballscrew systems operate much better at higher voltages. Your board supplies only 24v which will limit your system’s speed, unless you decide to use a pulley system, otherwise you’ll have to settle on lower speeds. That, shouldn’t impact your cutting speeds, but your rapids will definitely suffer.
I agree with @BartK about the high inductance. You’ll want to use a higher voltage to drive those motors to their full torque (need a new controller).
But… Are you saying that the motor spins fine when loose? And only binds when the housing is mounted?
After reading both of your comments I remembered reading somewhere that the rapids needed to be reduced.
I had to drop the rapids from 5000mm/min to 2000mm/ sec. It’s pretty slow but smooth and there is no grinding now. Still, it baffles my mind that the motors would run when not tightened down.
Voltage… I don’t run those steppers with 24v. They work ok at 24v, but are basically the same as the ones you replaced at that voltage, with that inductance, etc. To get the “full chooch” you need a different controller and power supply. It’s not hard, but it’s work and thinkage to put together. I’m running 48v, using a Toms Robotics board and it works great. Do NOT use one of the cheapo arduino “shield” boards. It’s not worth the time and debugging, they’re mostly clones of an older board that doesn’t support current grbl. If you’re going to do it, get something with a blue pill daughterboard on it, these are generally much more robust, the software port is pretty good, and can run at much higher speeds than the arduino 327’s can. I’m using this: GRBL GRBL32 3-Axis CNC Controller F13 – 250KHz – Tom's Robotics with external stepper drivers, which this board makes very easy with all interfaces exposed on screw terminals. Not the cheapest solution but I like the “just f’n works” aspect after messing with 3 different shield type boards.