Jogging in 1 direction is smooth and stutter free. Diagonals still stutter a lot. But when homing moves diagonally, it all runs smooth! Really weird..
Lets reconfirm if its a motor or mechanical issue. Disconnect leadscrews, do a diagonal move - check if if the motors run smooth (or not)
Agreed, so there must be a binding along either the lead screws or rails perhaps the machine itself is out of square? These motors are running smooth.
It seems there is some binding in the leadscrew nut-blocks. I had to shim between the bearing blocks and the plate to get it running smoothly, and now I have to shim these blocks too. Quite obvious in hindsight. The X-axis is all good now, already better
Unfortunately, the stutter is still there, even after shimming. At really low speeds it runs fine, but as soon as it gets above 1000 mm/minute, it starts to stutter like crazy again
Grbl setting still default (step timing and the like?) Applied a little PTFE (for example WD40 Dry Lube) to the leadscrew?
I just had this issue on a new Y table I made for my LEAD lathe so I can run it as a normal CNC. It was only one one of the two linear actuators so I figured it was not the acceleration rates. It went away after the application of the PTFE lube.
It seems there is some binding somewhere in the drive-system, so I think I will try lubricating them first, and if that doesn't help, I will rebuild the leadscrew-part.
@Peter Van Der Walt , I ordered some new cables, so I can mount the homing switches on the positions GRBL expects them, without having to apply a mask. It seems that the mask caused the stutter, because when homing the machine on stock settings it doesn’t stutter. I will place the X switch on the right-hand side, which is the maximum. Would you recommend the Y switch on the front or the back?
When I pull the switches of the machine, and click them with my hands, homing works! But when I put them on the machine, it doesn’t do the pull-off move, which it does when doing it manually. Any clue on that? Could it be a grounding issue?
@Peter Van Der Walt : I have been experimenting a lot with different settings, and I think I am on to something. I have checked 'step pulse invert' and that solved the stuttering. Now only the x-axis problem remains. When homing it does not back-up, and when running a g code, it does weird corners. Corners on the x-minus side go smooth, but when they are on the x-plus side, ie right side of the machine, it squares them of. When it is supposed to make a round corner, it just makes a square corner. I tried flipping arround the X and the Z axis, and then the problem of not backing up etc. moved to the z-axis. I also measured the stepper motor coils, they measured the same, about 2,3 ohms on both. Could it be that my blackbox has a defect on the X-port, and that it because of that doesnt move the stepper the right way? Is there a way that I can measure the pins? Thanks in advance!
