I’m having an issue with my Maslow 4. When I use the jog function, the top left arm makes small jerky or twitchy movements instead of moving smoothly.
but they are not continuous — they happen intermittently.
All other arms are fine — only this one has the problem.
I had already disassembled this arm before and found that the roller was broken (see photo). I repaired it by 3D printing a new end piece and inserting it inside, and it’s now strong and solid. However, the jerky movement problem is still there.
I also have a short video showing the issue if that helps.
Has anyone experienced this or know what could cause it?
Could it be related to calibration, motor control, or maybe something mechanical inside the arm?
Was it jerky there before you pulled the arm down?
It could be binding on the belt guard, in which case you might be able loosen the belt guard screws and move it around enough to clear the belt without having to pull the arm apart again.
You could also try pulling the belt right out, Do this by setting the retract force to a low figure (say 200) and extending and retracting until all the belt is out for that arm. Then reset the retract force to its normal value and apply a pressure as it retracts to ensure it packs properly.
I think that this is a good theory. It could also be a damaged gear slipping somewhere (probably inside the planetary gearbox on the end of the motor).
Does it behave normally when extending and retracting the belts?
Yes, the jerky movements were already there before I pulled the arm down.
It doesn’t seem to be binding on the belt guard — the belt moves freely and there’s no contact or friction there
I tried that procedure — I set the retract force to 200, extended and retracted the belt several times until it was fully out, then set the force back to normal and applied some pressure while it retracted.
I noticed that when I push the Maslow upward with about 8 kilos of force, it relieves the tension on the belts and the jerky movements disappear completely.
Do you have any advice on what could cause this or how to fix it properly?
Are you running in vertical mode? If so what is the angle of the work surface? Is that belt at a fairly steep angle towards the anchor point? Can you take a video which shows a bit more of the relationship of the Maslow to the work area it is running on?
In vertical mode the slope of the work surface needs to be greater than 25 degrees.
How tight do the belts feel? It could be an issue that they are too tight and running the process to find the anchor points again with a lower calibration force could fix it
Generally the fix for the belts getting slack in the corners is to use a larger calibration grid that gets closer to the corners. That will help it have more accurate movements there.
My experience suggests that the lower you can have the force, and still retract without problems, the better. I am on a horizontal surface and have set the retraction force and calibration force to 900 for each. You could also try setting Calibration grid to 2000x1000 & grid size to 9x9 and running Find Anchor Positions (previously Configuration) again
