7i96 stepper motor wiggle on plasma table

No, the wiggle was really really quick. But changing the P value to 1000 seems to have eliminated the wiggle problem now. I don't know what the P value means, but it did the trick.

Nick7251 wrote:

No, the wiggle was really really quick. But changing the P value to 1000 seems to have eliminated the wiggle problem now. I don't know what the P value means, but it did the trick.

Its great the team got you going while I was sleeping!
This amazing forum provides 24/7 support for free yet again!

P is the "proportional" in PID A feedback mechanism used extensively in industrial control. Linuxcnc still tracks positional error on steppers in a way which is way over my head but hey it works so I'm glad it did the trick!

Yes, thanks Rod for the push over to this forum, and thanks all for the awesome support.
Should I ask here where to go to change the direction of travel of the machine when I push the Right arrow? Basically my table is reference backwards right now. I want my (0,0) point to be in opposite physical corner than what it is.

You should be able to change direction by using negative values for STEPSCALE in your ini file
eg.

Rod showed you how to reverse it. But, on machines where the table moves, the right arrow should actually move the table LEFT, as what is important is that the cutting tool move rigth with respect to the workpiece. This takes a bit of getting used to, but it has to be that way for the machining of the workpiece to be correct, as designed in a CAD/CAM system.

The 0,0 of the workpiece coordinate system can be set anywhere on the workpiece with the touch-off button, or other methods in G-code such as G92.

Jon

Changing the Step_scale got the machine working in the direction I need. I am working on a plasma table, so my post processing software is what dictates direction of travel, and there is no concern of spindle rotation. Good point to bring up though. Thank you.

My machine is working as desired now. Speeds look good, I may bump acceleration up to be a bit faster. But overall I am very happy. Is it okay to load Plasmac on top before I calibrate the motors for travel distance?

Also should I load Plasmac or QtPlasmac? What is the difference?

Once 2.9 is released, QTPlasmac will be the only one supported. It is built from the ground up to be for plasma cutting but still in active development. I'm liking where its going.

You can. I would sort out your motion at this time as there is enough to worry about.

Now you are editing your ini file by hand, you only need to enter the number of steps per inch in the STEP_SCALE parameters so it should not take long if you can do the maths.
steps/rev
Drive Reduction
pinion diameter

Work out inches per rev, then the number of steps per inch

I did have to do some trial and error

I think my x and y are good. I copied those numbers from my Mach3 configuration, and it looks close. I will measure to make sure. I must have made an error copying my Y because it moves more than it should. So when I command it to move an inch, it moves around 1.5". I think I can find the issue and get it resolved pretty quickly now that I am getting familiar with the .ini files. I will get that all correct before I load QtPlasmac. Thanks again.