UM2 head can't move all the way to the right

[zolcos1 0]

I got the UM2 when it was new and used it moderately, it worked fine then. As of this morning I hadn't turned it on for at least 5 years. I updated the firmware then tried to do the leveling procedure and discovered that at certain points it stops moving and makes a bad buzzing sound like it's skipping/grinding the belts. Something starts preventing the belt-gear from rotating but I can't tell where exactly the resistance is coming from.

When this happens it also loses track of its position, so when going left it tries to move left when it's already at the left edge and makes the same sound.

Where should I start in getting it operational again?

 

 

[gr5 2,172]

I fixed someone's printer that was very similar to this.  It was friction on the larger diameter rods.  It took me a while to figure it out.  I just had to start taking it apart until I found the bearing that wouldn't slip.  It only took maybe 10 minutes?

 

First push the head around with power off and confirm that there is high friction.  Try some oil on all 6 rods (or at least the 3 X-rods).

 

Then next step is to pop out the 2 rods through the head - they pop out of the slider blocks - after all 4 are popped out, rotate the head 45 degrees and the head and rods can be lifted up out of the printer.  Check that they slide nicely.

 

Next is to loosen the 4 pulleys on the X axis and move the sliding blocks separately to see if one has high frictioner and the other low.

 

For me it was so bad I needed hammers and vices and such and I had to remove the sleeve bearing from one of the slider blocks.  It doesn't look as bad for you.

[Torgeir 242]

Hi zolcost1,

 

Just an observation, -looks like the X stepper is loose (the right one) it looks a little tilted up at the left side and the belt vibrate a lot on the right side when happening.

 

Thanks

 

Torgeir.

Edited October 2, 2020 by Torgeir
Spelling.

[gr5 2,172]

Interesting.  Maybe.  Or maybe it's just vibrations because the stepper vibrates strongly when it skips steps.

[zolcos1 0]

Thanks! Turns out I just had to oil the rods and it's printing fine again.