MPG Pendant very jumpy

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dreyfusduke

dreyfusduke
Hello, I'm having issues with my pendant wheel being very jumpy or jerky.

I have a new setup. Everything seems to be working fine. CNC router (previous Chinese DSP controller). I'm desperately trying to get it safely in production cutting lexan shields for local medical staff, etc.

I'm generating Gcode from Fusion 360 and so far I really like it.

I've got my "steps per revolution" set pretty close (I need to cut some calibration squares to really fine tune it but thats a later issue to work out). I've got my max speeds, and acceleration set pretty conservative. Movement during running the Gcode looks really smooth. Sounds beautiful. Cuts awesome.

I have my "pulses per revolution" set at 3000 per axis. (All axis have nema 34) .

The motor drives dip switches are set to 1600 (I didn't change any of that from previous Chinese setup).

The bad part is when I use the handwheel. It moves ... It's just really jumpy. Unpredictable. All the other videos I see people using it looks awesome. Smooth.

Example, moving any axis by cranking the wheel pretty fast results in surges and jumping. One tick at a time is fine.



Any ideas?
 
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dreyfusduke

dreyfusduke
Mine is also a 5 axis controller. I have it configured for use on a rather large cnc router that has a 4th axis as well. I have not even hooked up the 4th axis yet as I am still working on the table top getting it ready. I do have the Y and B axis slaved together and using a sensor on each side for the auto-squaring of the gantry. That is why I chose the 5 axis version. That seems to be working about as correctly as well.

I do have some questions about the "axis resolution" of the pulses per rev.... As I stated earlier, I have mine on 3000 for each axis. I can't really find a lot of literature explaining how to best set this. I know that more, or faster pulses = less torque for a stepper motor, but when I see some of the Youtube videos of people setting up their Masso, I see people using anything from 1000 to 6000. Any quick explanation of this?
 
breezy

breezy

Moderator
Quote from dreyfusduke on March 29, 2020, 1:14 am

I do have some questions about the "axis resolution" of the pulses per rev.... As I stated earlier, I have mine on 3000 for each axis. I can't really find a lot of literature explaining how to best set this. I know that more, or faster pulses = less torque for a stepper motor, but when I see some of the Youtube videos of people setting up their Masso, I see people using anything from 1000 to 6000. Any quick explanation of this?
Click to expand...

The setting in MASSO needs to match the setting in the driver, so if the driver requires 1600 pulse to rotate the motor one revolution, you need to tell MASSO that it requires 1600 pulses per rev.

MASSO uses the PPR and Distance per Revolution to calculate how many pulses need to be sent to move spindle the required distance. That is why you need to get DPR accurate and PPR correct.

In regards to the MPG, I'll leave that to Peter as he has access to the equipment to test it.

Regards,

Arie.
 
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dreyfusduke

dreyfusduke
Arie,

In my case, I believe this fixed my issue. After setting Masso to the same as my dip switches, the handwheel is much more reliable. It does as expected now. :)

I set the distances pretty close. Now I will cut some squares so I can fine tune it.

Thank you guys again for the wonderful support.



I would call this solved.
 
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dreyfusduke

dreyfusduke
Well.... Nevermind....

I changed everything to 1600 (per dip switch settings) and now another issue came up....

I ONLY changed the 3000 to 1600 and now just my Z axis will only move in the down direction no matter what. Even using mouse or MPG.

Ummm.... Bugs?
 
masso-support

masso-support

MASSO Support
Staff member
Hi @dreyfusduke

We currently have a ticket open for jumpy movement on the G3 using the MPG and you might have given a clue us with your resolution change so thank you. We are still working on this.

With regards the one direction of travel check that you didn't accidently disconnect your direction wire when changing your resolution setting. Changing resolution won't cause a one direction of travel issue but simply changing the resolution back will test if I'm right.

Cheers Peter
 
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dreyfusduke

dreyfusduke
It must be noted that this is a Chinese machine and I did find many critical wiring errors (on 220v side of things.) I'm going to go through everything tomorrow. Between Masso, the Chinese, and I....... I'm just going to check their wiring if you know what I mean.
 
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dreyfusduke

dreyfusduke
I added the 4th axis and it seems to be working well today. I went through every wire and every connection as well. While running code, the machine is very smooth. Still very very "jumpy" and surging while using the MPG though.

Hope that helps.
 
cncnutz

cncnutz

CNCnutz
Staff member
Out of curiosity what was the problem with the Z axis moving in one direction?

Cheers Peter
 
K

kozmanzan

kozmanzan
hello,

i have jumpy mpg also. steps per rev are set correctly based on screws pitch not by calibration so no mistakes there.

i have 5v mpg with a separate power supply.

let us know if you solve the problem. thanks!
 
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dreyfusduke

dreyfusduke
My pendent is pretty useless. Very unstable. Everything else is very good. I sent another email to Masso. I also included my settings file. Hopefully they can figure something out.
 
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safeairone

safeairone
Just to add another voice to this issue, I too found that jogging in continuous mode using my touch screen buttons was smooth, but using the Masso pendant MPG to jog resulted in sporadic axis movement (on both single-servo axis and axis with double/slaved servos). This was with software release 3.46.1.

I haven t yet tried it with the new release that came out today (v3.47).
 
cncnutz

cncnutz

CNCnutz
Staff member
The jogging should now work with the pendant MPG in the new software 3.47 release.

cheers Peter
 
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safeairone

safeairone
safeairone said:
Just to add another voice to this issue, I too found that jogging in continuous mode using my touch screen buttons was smooth, but using the Masso pendant MPG to jog resulted in sporadic axis movement (on both single-servo axis and axis with double/slaved servos). This was with software release 3.46.1.

I haven t yet tried it with the new release that came out today (v3.47).
Click to expand...
Just to put a final period on this topic...Even with update 3.47 and beyond, MPG handwheel jogging would still result in jerky, interrupted axis movement. That is, until this latest update (5.03), which I eventually got around to installing last month. Just noticed tonight that FINALLY, MPG jogging is smooth with the pendant, with absolutely NO interrupted axis movement when cranking the handwheel!

Nicely done, folks at Hind/Masso--Thanks for getting this worked out!(y)
 
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