[stevep43]

I just finished my cnc builds and all is well except while cutting contours with curves, my cnc starts to stutter for lack of better words. The cnc works well while moving in the x or the y, but not both at the same time. I have cycled through all the dip switch settings on the 5056 driver, but still no luck. Everything works well while cutting long passes on the x while stepping over on the y. Could someone please help. Do I need a bigger power supply? Different drivers? I'm at a loss.

Thanks, Steve

570 oz steppers,
36v 9a power supply
5056 drivers

[jueston]

are you experiencing this while cutting long straight diagonal lines, or circles and arcs?

sometimes something gets a little off on my code side and it will studder around corners, but then it will do fine everywhere else. this has nothing to do with the motors just my code most likely trying to achieve a high level of accuracy and making each corner a hundred little arcs which confuses mack3.

[Dan911]

Do you have CV on in Mach?

[louieatienza]

If you're using Mach, make sure it's not set to exact stop

[stevep43]

are you experiencing this while cutting long straight diagonal lines, or circles and arcs?

sometimes something gets a little off on my code side and it will stutter around corners, but then it will do fine everywhere else. this has nothing to do with the motors just my code most likely trying to achieve a high level of accuracy and making each corner a hundred little arcs which confuses mack3.

Here is what i noticed, When i change the current limit on the drivers, it get much worse. I am attempting to make Stratocaster guitar necks. The cnc performs flawlessly throught out the machining except for the last operation: cutting out the contour. There is a 3" arc at the end and that is where it has the most trouble. I probably have 100 hours on the cnc


Dan911
I'm not familiar with "CV"

louieatienza
I will check on the "exact stop setting"

Thank you.

[louieatienza]

You can set Mach3 to either exact stop or CV. For curves, CV usually beat. Also check look ahead setting.

[Devastator]

Check the "look ahead" setting. Mine works best set at ~200 lines. If this is too short, the buffer runs out and you get choppy curves.

[stevep43]

I have cv enabled. Look ahead set to 200. I have tried turning off cv and adding G64 to my code as someone suggested. Still no luck.

Here is a link to a short vid of my cnc misbehaving:

https://youtu.be/XE76b01N8Ec

Any help is appreciated. Thanks, Steve.

[louieatienza]

What's the CV angle setting set to? Also what CAM are you using?

[stevep43]

What's the CV angle setting set to? Also what CAM are you using?

Cv angle=0
Mastercam x8

[louieatienza]

Cv angle=0
Mastercam x8

Try a CV angle of 90. Mastercam X8... my God, what have we come to! If you can program MasterCam you should be able to figure this out!

[Devastator]

When outputting the g-code, what post processor format are you using? Certain formats might be adding code that overrides your mach settings.

Like:
G08 P1 = Look ahead control ON
G08 P0 = Look ahead control OFF

You might want to look at your code to see if you can spot any thing suspicious.

[gfacer2]

Just to rule out things, the file doesn't consist of tiny lines rather than arcs or arcs with a million nodes? I've had both issues on files I've imported from other formats.

Sent from my LG-D852 using Tapatalk

[Jon.N.CNC]

Just to rule out things, the file doesn't consist of tiny lines rather than arcs or arcs with a million nodes? I've had both issues on files I've imported from other formats.

Sent from my LG-D852 using Tapatalk

I get the same stuttering intermittently, one pass it will be fine the next it will do it in certain spots. People have suggested getting a better graphics card in pc, I'm not so sure this will help but will let you know when I've tried it.

I've tested voltage at psu, my machine runs off both AC and DC, and both stay very stable during these moves so in my case not a power issue.

Leads me to think it's code, motion controller or pc based.

[louieatienza]

Just to rule out things, the file doesn't consist of tiny lines rather than arcs or arcs with a million nodes? I've had both issues on files I've imported from other formats.

Sent from my LG-D852 using Tapatalk

Shouldn't matter if CV is on and have decent look ahead. Unless maybe steps/unit is set ridiculously high because of excessive microstep resolution.

[A_Camera]

If you're using Mach, make sure it's not set to exact stop

...unless you need to have it exact stop...

That is what I use and that is what gives the best precision. Constant speed may not always be suitable.

[A_Camera]

I have cv enabled. Look ahead set to 200. I have tried turning off cv and adding G64 to my code as someone suggested. Still no luck.

Here is a link to a short vid of my cnc misbehaving:

https://youtu.be/XE76b01N8Ec

Any help is appreciated. Thanks, Steve.

Do you mean the "clonk clonk" sound at 13 seconds mark? To my ears everything else sounds normal. The cutting of curves sound always different from cutting in straight lines.

[stevep43]

Do you mean the "clonk clonk" sound at 13 seconds mark? To my ears everything else sounds normal. The cutting of curves sound always different from cutting in straight lines.

No, not the sound at 13 seconds. It's more the way it travels around the curves. It's not very smooth and i get a very jagged edge on the contour.

[plcamp]

You can set Mach3 to either exact stop or CV. For curves, CV usually beat. Also check look ahead setting.

CV=Constant Velocity

[A_Camera]

No, not the sound at 13 seconds. It's more the way it travels around the curves. It's not very smooth and i get a very jagged edge on the contour.

Oh, I see. Well, in my opinion that's perfectly normal. It depends on how the G-code is written, and how the curves are generated. I include my own video, listen to the sound. When the letters are written, it sounds like yours and when the circles are drawn it sound like a whining. That's because the difference in the code and how the motors are used. Perfectly normal in my opinion.

https://youtu.be/ItUOqsYaRB4