Short Belt Adjustments

[chrisp 10]

I spent a little time looking for a previous post on how to adjust the tension of the short belts on an Ultimaker 2. I couldn't find anything.

The short belt located on the back-right side of my UM2 is loose. I decided to check it after noticing that my circular holes in my prints are a little oval and not so round.

Can anyone point me in the right direction or explain to me the best way to go about tightening up this short belt? Or is there another option to adjusting settings in Cura or through the control panel?

 

[jonnybischof 60]

There's the possibility to (ab)use an idler pulley bearing: You could mount one in a way that it scretches the timing belt, though there's probably very little space. I don't know the UM2 in detail, you can probably see better whether that would work or not.

Idler pulley bearings come in various sizes, maybe you can just put a small one in the middle between the pulleys, and then slide it out of center so that the timing belt will form a triangle.

Then you could go all engineery and mount the idler pulley with a spring, controlling the belt tension nicely

 

[sigi 0]

I spent a little time looking for a previous post on how to adjust the tension of the short belts on an Ultimaker 2. I couldn't find anything.

The short belt located on the back-right side of my UM2 is loose. I decided to check it after noticing that my circular holes in my prints are a little oval and not so round.

Can anyone point me in the right direction or explain to me the best way to go about tightening up this short belt? Or is there another option to adjusting settings in Cura or through the control panel?

 

That might have happened because the screws of the stepper motor got loose. On the back side of the UM2 you see the four screws going to the stepper motor. Open them slight, push the stepper motor down and tighten the screws again.

I had an issue with the pulley of the left stepper motor and realized that the screws were not tightened too strong.

This issue was described in this post:

http://umforum.ultimaker.com/index.php?/topic/4171-ultimaker2-axis-squeeknoise-solved/

 

[gr5 2,210]

The X and Y steppers should be mounted in slotted holes so that the stepper can slide up and down a small amount. Like sigi says: loosen the 4 screws, slide down the motor so the belt is very tight and then tighten the 4 screws. If this isn't enough you need to lengthen the slots with a hand drill and router bit.

 

[jonnybischof 60]

It's a little bit easier that way

 

[chrisp 10]

Thanks for the ideas guys, but the holes either have to be drilled out more, or I need to replace the belt. The easy way did not work.

[gr5 2,210]

Get a router bit at your local hardware store. One that is the same diameter as the existing slot.

 

[chrisp 10]

I have the necessary tools, just didn't want to go that route to fix it.

At any rate.....thanks for the ideas.