How tight should a sliding block be against the axis?

[astrodenny 0]

When tightening each slider block how tight should the inserts (marked C) be against the axis? Should there be some play so the axis is slightly loose or should it be as tight as possible? I just wanted to confirm. Thanks!

 

[gr5 2,234]

Part C is called a "claw". You really have to tighten completely otherwise it won't clamp the rod properly.

When you assemble that piece, the current instructions suggest one nut on each side along with the screw head.

If you want to tighten your belts more you loosen that screw so the head sticks out more. This is how I tightened my belts and haven't needed anything else yet. Except I might have added a slightly longer screw (this may have involved a hack saw to get the right length - I don't remember).

This links directly to the claw assembly I'm talking about:

http://wiki.ultimaker.com/Ultimaker_rev.4_assembly:_X-Y_axes#Step_2:_The_claws

 

[astrodenny 0]

Let me rephrase - I understand the claw and its concept, but I was curious to know if there should be any play in the rods. When you tighten the C clamps down for belt tension, it tightens up the rod as well. Should the rods be completely tight or should there be any loosness or play? I noticed that in the directions you have to find a happy medium between the belts being too tight or too loose. But any additional tightening also seems to effect the rods being too loose or too tight. I guess I'm trying to find the happy medium so that the rods don't shift in the slider blocks.

 

[renelm 0]

I'm having the exact same question as well.. using the claws both to tighten the belts and restrain the rotational movement of the sliding blocks is a kind of a hen&egg situation as the instructions (with video) clearly state not to tighten the belts too much, which on my machine results in the rods having quite a bit of play.

So far my prints look fine, but I'm worried if there are going to be any visible artifacts in larger prints from this play..

Cheers

PS: Really really really really happy about the machine. The prints really look and feel great, even when actively slicing low quality prints. Love it

 

[gr5 2,234]

As I said before you want them as tight as they can go. If this means the belt is getting too tight then you can probably remove the little scew and nut that increases belt tension when these blocks are tight.

[aaron 2]

Just to throw in my two cents, I cave mine all as tight as they will go and do not have any friction issues. There is a small thread about friction and alignment here if it helps: http://umforum.ultimaker.com/index.php?/topic/2589-axis-alignment-problem/ (please read to the end)