I just put in the x and y axis in my big box and it sounds like the y axis bearings are binding when it gets within2-3 inches of the rear, I have everything loosened and it still does it... It basically just becomes choppy and sticky, almost like there is something wrong with the bearing, but it slides just fine the rest of the y axis...
Okay so, apparently those linear bearings allow axial rotation in one direction, so to fix I just took the bearing off the rod and flipped it around.
I've noticed the same problem. @Chase.Wichert, did you reverse both bearings? Will there be a similar problem with the bearings in the build table?
Just the one that was skipping, it was pretty noticeable which one it was. I believe it is just how the bearings are. If they are both doing it then go ahead and reverse both, But I would just try one at a time.
I was already beyond the step of installing the Y axis belts, as I'd thought maybe the binding was attributable to things not being tightened/trued up yet. It wasn't fun taking things apart. I'm still not convinced I've completely solved the problem, though it does feel better. Would have been a nice note to have included in the build instructions! Thanks for your help.
No problem, after I flipped one, it was like butter, I had it all loosened up and was tweaking the frame and nothing really helped so I figured it was something with the bearing.
I wonder if just taking the bearing off and putting it back in the same orientation would have helped too? I don't know of any explanation of the direction-sensitivity of the function of a linear bearing. Interesting how the long term stability of these bearings will look. Either, the problems you had can be traced back to any residual foreign matter remaining from the fabrication process, which shouldn't happen either, or the handling of the bearings, e.g. how to insert the rods into them correctly, is the source of those issues.
Ive notice the same problem creep back in, I replace it with another bearing and all seems well. So I may need to buy some online...
Email support, Catriona is great getting replacement stuff to you quickly (for me it has been missing, and one broken).
I ended up buying a pack of 4 from Amazon, should be here tomorrow. Hopefully one of the 4 will work. Or maybe even the bad one will work just fine in the z axis, being vertical...
Yeah I am sick of taking the printer apart to get to the x/y axis, I think I have done it 3 times already. One was my fault, and of them were the bearings fault.
Once I replaced my Y axis bearings I haven't needed to take apart the axis again. I wonder if the Y rods are suffering from similar issues that the Z had but it shows up more in bearing failure.
I haven't received the ones I ordered from Amazon, however the bearing that was bad in the Y, I moved to the Z, and put a different one in the Y. All is good now. That and I added white lithium grease to everything.
*BINDING SOLUTION: If your X Axis Assembly bearings seems to bind as it approaches the Rear Y Axis Assembly it is because the spacing of the Rear Y Axis Assembly Brackets is wider than the distance between the 2 bearing brackets on the X Axis Assembly. First loosen the screws holding the rods/rails of the X Axis on both the R/S an L/S X Axis Assembly Brackets where the left and right bearing are. Then follow the assembly instructions as noted in the manual to install the XY Axis Assembly. Before you finish just push the X Axis Assembly back and forth and back again to the Rear Y Axis Assembly. This will cause the X Axis Assembly brackets to stretch out on the rods/rails and self adjust to the same width as all the brackets and your bearings will then be smooth and slippery as butter. Don't forget to retighten the screws that holds the rods/rails on both the R/S and L/S of the X Axis Assembly Brackets
During that final assembly process I had extremely lumpy Y movement, toward the back part as described above. I didn't have my mind around everything that works together at that stage, but as I went through the commissioning process everything just got smoother and smoother. I don't relish the idea of having to redo that, but it's always a double-edged sword. The pain of assembling often teaches you something. Given Chase's recommendation on thread locker, I have a feeling i'll need to check all screw regularly and maybe at some point disassemble in order to apply some myself. I'll wait till I have that problem first.
I had to replace all 8 crappy bearings with new ones. Actually Amazon carries, both, cheap and quality bearings and Servo City is great. I had made a video of the bad bearings to show E3D and was told that they were in talks about the bearings but that was the last I heard of it. I can only assume they are well aware that the bearings are not cutting the mustard.