New GF alignment/track issue

The attached pic is the result of the first part of recalibration after having alignment/track issues.
I just got this replacement machine and all 3 prints have been off on alignment. After researching, I attempted a recalibration, but the problem seems to be physical. When the gantry attempts to move towards the back, one side gets bogged down, causing the gantry to jam up, stopping short of its target.
The problem is also present during the initial startup process. Pretty much any time it attempts to move towards the back, it gives out a rough grinding sound and stops short.

I have taken an up-close look at the tracks and wheels but do not see any obvious culprits. It does seem quite stiff/resistant to my manually pushing and pulling the gantry along the track, but I’m not sure what is normal for that.

Please someone tell me this can be resolved with a simple pulley/belt adjustment or something like that and not that I need to go through the replacement process again…
Thank you in advance.

I’ve managed to do a couple successful prints but only by minimizing the amount of back and forth movement involved. When it tries to move too far too fast, that’s when it gets jammed up. But moving across the same distance at a slower speed (like while engraving) seems doable.

GF 2-11-22A

It’s physically being stopped by something, and you’ll need to figure out what (or ship it back). My guess would be that it’s running into or snagging on a wire harness or coolant line somewhere on the left side. You may need to get in there with a light and a camera to see what’s going on past the lid opening.

If the machine is turned on, there should be a lot of resistance to you moving it by hand, and you shouldn’t try it. If the machine is turned off, there should be no resistance to moving beyond the tension of the belts, it should slide along the rails easily.


Hi, thanks for replying.
After taking a closer look and repeatedly going through the start-up, I’m fairly sure that something is interfering with one of the belts that moves the gantry forward and back. Once the gantry gets about 3/4 of the way back, there is a grinding noise which I’m thinking is something rubbing across the teeth of the belt (or the belt teeth rubbing across other teeth?). It’s acting like one component is trying to move the gantry back, but another component is attempting to stop it, like a miscommunication or something.

I should note also that I can move the gantry by hand with no issues while the machine is powered off. There is no interference or grinding noise. It only has the issue while powered on/moving on its own.

Another observation I had was that the back wheels for the belts responsible for forward/back movement don’t spin with the belt. They are very stiff. I can spin them by hand with a tight grip, but the machine/belt doesn’t spin them. I would assume they are supposed to spin freely to avoid friction on the belt teeth but could be wrong.

They are fairly powerful stepper motors and by their very nature hard to turn by hand. Should be impossible when powered on (don’t advise you try it…)

The smooth wheels in the back are the ones I’m talking about. They don’t spin at all during operation. The toothed wheels at the front seem to be working as they should.

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