Extruder head hard to move

[banana97 0]

Hi Guys - so I printed and installed some belt tensioners to get the belts to "sing" as per the instruction video. I also realigned the axes - but now I find that there is a lot of resistance in trying to move the head by hand. It isn't free at all as shown in the assembly video.

With the lower belt tension (which was very low) the head felt less resistive (obviously) so I'm not sure if there is something I have missed - or use less tension in the belts?

[ian 32]

to be honest, a lot of ultimakers that i have seen, have tight belts and dont move like butter.

make sure there is a little oil on those bars and the oil moves around the axis.

Then test....

if there is no problem, then super.

if your motors are room themprature to touch and seem under powered, when the belts are in tension, then you could increase the voltage a tiny bit to the motors and balance your system out that way !

check the wiki about that !

good luck.

Ian

[banana97 0]

Motors get hot so if anything i'd say they are being stressed too much?

I'll try and lubricate the axes to see if that helps.

[ian 32]

how tight are the rubber belts ?

when right, they should twang like a guiatar.

Ian

[xonegon 0]

Hi , I've got the same issue & I've made a video about it...

 

Is it the same problem you are experiencing ?

did you find a way to solve it?

[jsamuels 0]

If the clicking is coming from the back-right pulley you're pointing out in the video, try loosening the grub screw for it and moving the axis, to see if the clicking goes away?

Did you already check these things?

- Short belt tension

- Rods and belts are in the same plane along Z axis... this thing will demonstrate :

http://www.thingiverse.com/thing:8781

- Belts aren't binding on or rubbing the shoulder of the pulleys, and that the pulleys themselves aren't rubbing against the rod end bearings / frame.

- The rod end bearings or rod ends themselves are not rubbing against the covers on the outside of the case.

After you installed the belt tensioners, did you loosen all pulleys to allow the tension to equalize? If not then you would have more tension on the lower belt segment than you would on the top.

[banana97 0]

I reduced the tension in the belts and the head was easier to move. I will do some calibration prints to check.

[bob 0]

I have the same issue seen in Xonegons video (irregular head moving resistance) I just built my ultimaker yesterday, so I dont even know if it works, but my guess is that as hard as the head is to move by hand, the prints wount turn out very well... the outer rods with belts move very well by them selves, when the head is not attached, so Im guessing that the axels which go threw the head are putting pressure on the outer rods. Any thoughts about this would be appreciated.

Update: I tested my UM yesterday and I also heard some clicking sounds, though only a few. also wobbles and irregularties were visible in the print at certain positions.

below an example of the resulting print (my first one):

you can see iregularties all along the right arm

[snowygrouch 1]

First you are not putting out enough plastic.

Regarding the head, its very likely that your axle wooden blocks that run up and down the rods, are

misaligned. This cannot be done properly "by eye", so find some sort of "spacer" to put between the

frame and the XY rods for the head. So you can square them up properly with the belts loostened.

See picture. One or both of your XY rods are probably as shown by the red lines here.

[bob 0]

I realigned the rods again yesterday and the result was much better, unfortunately it seems that I now messed something else up as the whole print is slanted :-o

[snowygrouch 1]

Do you have a dial gauge ?

[bob 0]

unfortunately not :(