Weird Belt Tension

[eric-lester 1]

So I noticed this a while ago, but it hasn't really had any bearing on my printer as far as I can tell. Basically, the frontmost belt (in traditional Cartesian the x-axis) is tight along the top but loose along the bottom. Take a look:

I'm obviously quite concerned about it, but after running several prints and carefully watching, there's literally no slipping due to the tautness along the top of the belt. Obviously, I don't want to try to fix what's not broken and ruin it (especially with a big influx of orders for stuff right now), but I'm curious as to what can be done.

 

[IRobertI 438]

I've seen this on one printer before. It's easy to fix, just loosen the screw on one of the pulleys that the belt runs over, the tension will equalize over the top and bottom and you can then re-tighten the screw again (hard).

 

[eric-lester 1]

just loosen the screw on one of the pulleys that the belt runs over, the tension will equalize over the top and bottom

 

Which screw are you talking about? Also if the tensions equalize, then won't it no longer be taut along the top?

[IRobertI 438]

On the pulley that the belt runs over in the corner of the machine there's a small set screw. You'll likely have to move the head a bit so that it spins into view. Loosen that screw and the pulley will be able to spin freely on the rod. Make sure you tighten the screw tightly afterwards.

The black sliding block has a spring inside it that keeps the belt at the correct tension so it wont be a problem.

 

[eric-lester 1]

Ah I see what you're talking about. Does that screw just use pressure to say set? I assumed it ran into a hole in the axle.

[IRobertI 438]

Just pressure I'm afraid.