Belt maintenance

[Mithartridge 0]

Hello,

We have the ultimaker 2 Extended. The back belt is running a bit saggy and we just wanted to tense it up again.

Just wondered if anyone had a way to do this and some tips before we dive in.

Mitch

(Blue Box Energy)

[IRobertI 454]

I assume you mean the long belt? If it's the short one you simply loosen the four screws that hold the stepper motor in place, press down firmly on the stepper and then re-tighten.

For the long belt; is the belt slack on both the upper and lower part of the loop? If it's just one side you'll have to loosen one of the pulleys that the belt runs across so that the pressure can equalise and then re-tighten the set screw again (firmly!).

If that's not it something must've happened inside the slide block. The slide blocks contain a spring that should keep the belt at the proper tightness automatically. Unfortunately it's difficult (if not impossible) to open those up without snapping at least one of the little tabs that keeps it shut so I would maybe try to improvise some external belt tensioning device. Not sure how much space there is to work with though.

[hreedijk 4]

If the slack is on both the upper and lower part, get some of these:

Set the X and Y axis in the middle of the printer, loosen 1 pulley, add the spring above the slide block, tighten the pulley again.

Be sure that the most flat side is at the slide block, otherwise the belt can touch the axis.

[MrLunk 0]

There are a lot of 'Belt tensioners'on Thingiverse...

http://www.thingiverse.com/search?q=ultimaker+belt+tensioner

PL.