Centroid Community CNC Support Forum

It tells you you over torqued the motor on one of your pics. I assume you got 4 yellow blinks on the motor when this happened?

Did you consult with Teknic on your machine, gantry weights, z axis weights and other info before you selected the motor you have or did you just randomly pic a motor thinking it would work? Just because it's a SDSK 34 does not mean it'll work.

If it wont autotune and it faults, what is the fault you get on the motor when doing that? 4 yellow blinks again? One cause of this is an "undersized motor" and is probably the root cause if you say the mechanics are good. Do you have the room to add a counterbalance to the Z axis?

Hi Shawn,

Yes 4 blinks. The torque ramps right up when jogging upward in Z then once past 90 or so it alarms out of the MSP tune

I bought the machine with motors already on it.
It has always faulted z axis

I did fill the machine with epoxy granite after purchase though. It faults far more than before to the point its unusable.

I actually started building a counter balance over the week end hoping that will resolve the shut down motor.

I will load images when done waiting for cable clamps. Should be there when I get home today.

Thanks bro

Thanks for the info. That tells me whoever built it didn't do their homework. I know many people whom I've retrofit machine for just hop on Amazon, find a drive/motor combo that looks nice and say to themselves "hmmm, that should work" and they end up with machines plagued with issues and wonder why it doesn't cut right or even work right.

In your case, if the drive always faulted before then filling it with dead weight only made matters worse.

Is there a gearbox on the Z axis? What kind of machine is this?

A gearbox would help but it will slow the axis down. Maybe not as important if this is a mill and not a router. The counter balance will also work if designed properly.

Lol,

Yeah, starting to wonder about motor choice too.

This is a precision matthews PM940V not a gear head and no gearbox on Z.

The head was probably 50lbs heavier after the partial fill

I would certainly wonder about why the builder chose that motor. The Clearpath motors are AWESOME when you spec out the correct motor size for the loads and speeds.

I just Googled the part number for your mill and it looks a lot like a Grizzly G0704 I used to have.

Can you add a 5:1 or 10:1 gearbox to the Z axis? Any pics that show how the Z motor is mounted on this mill? I'm just a dumb router guy.

mectecmike added a counter balance to his 727

https://centroidcncforum.com/viewtopic.php?f=57&t=3376

Shawn

I probably could add a gear box, but If this Frankenstein counter weight system Im making(with a drill press)solves the issue. I will design a better one in CAD then machine all the parts. If it doesn't I might purchase a different motor from Teknic.

Here is the pic of it so far. Again this is a "roughing" for testing. Don't laugh. Just want to see if it helps. I'm sure it will because the z never has failed this much. I forgot to mention I put a power draw bar on it too. Everything is dangling right now.

Keith,
I watched that video a while back.
He did an awesome job on it!

What's that? Just kidding, you have to experiment with the counterbalance for sure to get it right.

The counter balance will certainly work. With your pulleys and cables you can easily determine the amount of force or weight you need to balance it. Once you calculate it with dead weight you can always then look for some gas struts that have similar force for a cleaner look with less moving parts. But either way will work. I added an air cylinder with a regulator to a router retrofit once for an infinitely adjustable counterbalance on the very heavy Z axis and it worked well. An industrial router I rebuilt once had the same setup and it worked really well so I just sort of copied it.

You also clearly have the room for a planetary gearbox on there, that would certainly make a difference as well with minimal expense and work.