[Semus]

Hey guys,

I usually contact CNCRP directly, but I wanted to see if anyone else has run into this issue.

I just built a new PRO4824 setup (Actually, it's 24x48 - I requested that the X-Axis be longer than the Y-Axis). I don't know if the different configuration has anything to do with this, but I'm not expert.

It seems that when I tighten down the bolts that keep tension on the motor/rack gears, I get binding if I tighten them too tight. I tightened them down no more than what the instructions recommended (by hand - then 3 full turns), and even that seems like it's causing some binding. I had to loosen the bolts a bit in order for the motors to stop binding.

I noticed this morning that if I move the X-Axis back and forth at rapid speeds from one end of the track to the other (I only have mine set to 600ipm), the motors will bind (act as if they've crashed into a bump stop). I thought it might be debris on the track, or some interference, but nothing is on the track, and nothing is in the way. The only thing that seemed to solve the issue was to loosen those tension bolts quite a bit.

The bolts aren't so loose that the gears are dangling there, but I'm worried about the tension being less than specified in the instructions. I'm also worried about loosing some accuracy, or gaining unnecessary backlash.

I had no idea that tightening those tension bolts could cause the motors to stall like this. I'm only using the NEMA 23 motors, and I realize that aren't as powerful as the NEMA 34's.

Perhaps I could up the power a bit on the NEMA 23's somehow? No idea if that's even possible. Just wondering if there's something I can do besides loosening those bolts.

Any suggestions?

[Goonk]

Hmm. I am very new to this, but I just finsihed my build a couple of months ago. My X is the 48" too (Standard machine). I tend to overthighten. My springs are very tight. No issues at all at full speed moves. Could the motors not be synched correctly? Are your slave settings correct? Is your X and Y nice and perpendicular? I would check to make sure ALL of the slave and primary settings are identical and that the Slave A or B is chosen, etc.

Good luck! I'm sure CNCRP will reply and know what the issue is right away.

Tony

[ahren]

Hi Chris,

600 IPM is getting up near the top end speed of a Nema 23 system. With any stepper motor, torque falls off as speed increases, so the system will be more sensitive to resistance from any source at higher speeds. Additionally, if you just greased your bearing blocks, this can add some resistance temporarily until things move back and forth a bit. You can run with a little less tension on the R&P drives as well -- there's a pretty big window for this setting, so backing these off shouldn't cause too much trouble.

If I recall, you are using your original controller from back in 2014, and are using the 3.5A motors we sold at that time. The 4.2A motors we now sell have just a little extra torque that can make a small difference at these higher speeds.

To make a long story short, to keep things as reliable as possible, I'd recommend decreasing your rapids to 500 IPM, which will still be quite fast but will put you in a safe part of the torque curve for your motors. At cutting speeds, the motors will be in a much better place in terms of torque, so you shouldn't have any issues here, and this should have a minimal impact on your machine's productivity,


Best regards,

Ahren
CNCRouterParts

[Semus]

Hi Chris,

600 IPM is getting up near the top end speed of a Nema 23 system. With any stepper motor, torque falls off as speed increases, so the system will be more sensitive to resistance from any source at higher speeds. Additionally, if you just greased your bearing blocks, this can add some resistance temporarily until things move back and forth a bit. You can run with a little less tension on the R&P drives as well -- there's a pretty big window for this setting, so backing these off shouldn't cause too much trouble.

If I recall, you are using your original controller from back in 2014, and are using the 3.5A motors we sold at that time. The 4.2A motors we now sell have just a little extra torque that can make a small difference at these higher speeds.

To make a long story short, to keep things as reliable as possible, I'd recommend decreasing your rapids to 500 IPM, which will still be quite fast but will put you in a safe part of the torque curve for your motors. At cutting speeds, the motors will be in a much better place in terms of torque, so you shouldn't have any issues here, and this should have a minimal impact on your machine's productivity,


Best regards,

Ahren
CNCRouterParts

I appreciate the info, Ahren. Sounds like I need a motor upgrade if I want to run at these speeds. What exactly is involved in upgrading the motors? Would I just need the motors themselves, or would I need to replace the entire electronics kit?