Inner and outer profiles not touching

[IRobertI 521]

Right, I'm officially going crazy. For the past couple of nights I've been trying to fix this problem with misalignment. I'm not sure how to explain it in words so take a look at the picture I've attached to see what I mean. As you can see the top right and lower left corner prints just fine (it looks really messy but that's mostly the flash exaggerating the imperfections). However, the bottom right and top left are wider and there's a void inbetween the inner and outer profile.

I've been trying to increase and decrease the tension of the belts but it seems nothing I try is helping. I've tried having them both very lose and as tight as I could get them (the belts starts rubbing against the top of the printer). When I had them tight I had to increase the current to one of the steppers a little tiny bit as it stalled occasionally (just resting a finger against the print head was enough to overcome it), no motors are getting hot though.

I've aligned the axes to the best of my ability and as far as I can tell they are square. However, if I center the head in the left-right direction and then try to move the head from front to back and back it binds a bit. When it gets moving though it doesn't seem to be any problem moving it around randomly, it is quite stiff though but as I understand it that's the case with the newest batches. If I have the head fully to the left or right the problem goes away.

The axes are lubed with a very thin layer of the lube that came with the printer. I find that I have to use a very very thin layer or the motors stall out. It seems to me some grease with lower viscosity would be a better match for this printer.

Oh and btw, the picture shows the part as you would see it if you were looking down on it in the printer while standing in front of it. The part is roughly 7,5x5cm.

There, I think I've covered the details, if not let me know and I'll try to answer. So, where do I go from here?

[joergen 2]

this is more a slicer issue than a mechanical issue, i think.

and it depends on the extrusion thickness, and the thickness of your object.

for example, if you have a 1.2mm thick object, and you or the slicer are using 0.5mm extrusions, then the software has no other choice than to leave a 0.2mm gap between the shells...

[IRobertI 521]

That's true, but, if that was the issue wouldn't that be happening around the whole object? This is happening only in the top left and lower right corners. The other corners look as expected and their thickness matches the model, the faulty corners are slightly fatter so to speak and have the space between them.

[owen 19]

I can't see the problem in the pic. but about your belts, you definitely want them tight, not loose.

I also had a a problem of tightness in spots when moving the head back and forth after changing my X and Y motors.

It turned out it was where the coupling on the motor shaft was positioned.

Although it looked aligned with the belt and coupling on the other shaft when I move that coupling along the shaft a bit it fixed the problem.

[IRobertI 521]

I got in touch with my inner child and doodled a bit on the picture to clarify. It's a bit exaggerated but I think you get the idea.

Thanks for the tip about the coupling, I'll have to take a look at that.