8mm Igus Drylin RJ4JP-01-08 - 3D Printer Solid Polymer LM8UU Bearing (4)

I bought these about 6 months ago when I built my own Original Prusa Clone using the bear upgrade frame.When it came to bearings, I was aware of cheap 'n nasties from China, and didn't want to use them. So, settled on these.They are quiet, and they are smooth. And for most applications, these would be ideal. However, I found that they have too much play on the Y axis, that the bed had far too much play - a lot more than a Original Prusa. There's also a little play on the extruder body.I decided to replace with IKO Japanese LM-8UU bearings, that were much more costly, however all my axis are now firm. Quality of prints also increased, which I was hoping for but didn't expect. Sure, the new bearings aren't as quiet, nor as cheap, but as the printer is kept in a Lack enclosure, it's not a problem.The bottom line is, if you want things to spec, with tight tolerances, then don't use these. Yes they are quiet, but on 3D printers where precision is key with such small print diameters, then don't bother with this. Get quality ball bearings and build an enclosure.

I replaced the original noisy, notchy and poor linear bearings provided with the 3D printer with these Igus bearings. I was not disappointed, they are near silent, smooth in operation and providing you set them up correctly, otherwise they can bind due to their tighter tolerances, they are perfect. I used them on the X & Y axis and found that over tightening the bed to get it level actually put upward pressure on the Y bearings, that then made them bind. My mistake, the acrylic bed carrier was actually being slightly pulled up, which pulled the bearings up causing the binding. Resetting the bed tensioning to a much lower tension, solved the problem. Subsequently I replaced the acrylic bed carrier with an aluminium one, as the flexing is not good, this solved the problem. This would have been an issue with the old bearings but harder to detect as though they appeared to be working they actually masked the flexing.

Perfect.Had to trim mine down to fit my printers carriage but they have removed a significant amount of noise from the machine. I would say they are a little stiffer than a standard ball bearing, but do move without any binding. They were the same diameter externally as my bearings but have read that the LM8UU can vary, so worth double checking.Mine clipped in place into the carriage fine, and after cutting feels like they are a sturdy replacement. The 12 pack has allowed me to do all 3 axis on my CTC printer.I have reduced the noise which is great as my 3D printer is right next to where I work all day, but will the additional stiffness cause extra strain on the motors? Time will tell I guess, I am hoping they will 'bed in' a bit and it will be fine. When you put one on the steel rod and compare it directly to the noise a standard bearing makes you will feel instantly as though you made the right choice.

these bearings are designed to be compression fitted with a 40 kg weight. that will compress the bearing just the right amount, as designed, to grip on the surface of the rod with no wiggle room. whereas with any 3D printer I know bearings are not compression fitted (usually held in place by screw or a stop ring) this will leave you with some wiggle room and you know the rest ...

Using on my Anet A8 3D printer to replace the linear ball bearings.Quite surprised to see a bushing bring sold to replace a linear ball bearing but a friend had them and said they're quieter. I now agree. Still miles quieter than the stepper motors and the fans so the change isn't massively noticed. Can't speak for the wear but I'd expect it to be worse than the ball races, time will tell.In the short term, highly recommend

I got these to replace the linear bearings on a Prusa i3 Mk3 3D Printer, as I found the supplied ones a little 'scratchy' and noisy.I disassembled the printer as required to exchange the bearings for these on all 3 axes. I wiped the rods with a PTFE lubricant before fitting, and re-assembled.Apart from the odd squeak - which is when the bed is doing very short back-and-forth movements - they are silent, and glide very smoothly. These are a definite improvement over the standard linear ball bearings and I would recommend anyone with a 3D printer to use them.

Bought these after my stock Anet A8 bearings started grinding. Wish I had bought them sooner as they might have saved me having to buy more rods.They run smooth as silk and are extremely quiet

work amazingly, couldn't recommend them enough!