Linear Motion Ball Bearing Slide Block, SCS20UU 20mm Pillow Block Closed Linear Bearing Aluminum Bushing Linear Rail Support Guide Shaft Bearing for CNC 3D Printer Parts 4 Pack

These fit well on 10mm rod with no backlash/slop and very little friction. The mounting holes are threaded, in case that’s not clear from the description.

The plastic rails that came with my 3018 were warped and never tracked smooth. I replaced with this product and now a very smooth operation

I ordered four and three seem perfect but one is grumbling when in use. Cheap as they are I'll not go through the trouble of a return but order more and perhaps end up with a couple of spares. I will, however, look for another seller.

Excelente

These bearings have the normal dimensions for SCS bearings and are bolt-in replacements for my 3D printer. The 8mm ones I got have four rows of balls, which is typical. Smooth operation. The seals are tight enough to scrape dust and detritus off the rails and keep the bearing clean inside. They came individually sealed in plastic bags to keep them clean and dry. They were not covered in oil like some other brands I've bought before. Makes installing them much faster as I don't have to clean that all off. Just add a little grease inside, and bolt in place.

Unfortunately I received unthreaded slide blocks screws hole, which was very disappointing, the bearing quality to be honest was great, and very smooth.

not a ball bearing

The HiPicco Linear Slide Blocks arrived in a plain box with each block individually wrapped. Each one had a thin layer of lubricant on and in them. Upon inspection, this set is not machined to super tight tolerances. Each exhibited a few rough edges, burs or scuffs. I tested a few shafts with the blocks and the linear movement was good enough for my prototyping needs. I didn't notice any huge wobbling, jamming or grinding while testing. These would be perfect for tinkerers or DIYers.

Super

These worked very well providing a smooth ball race on a 20mm steel shaft

Toupies glisse facilement.

As described. Work well

I got these to use on a project running on 15mm copper pipe so my needs were never going to be precise, these are perfectly fine for that kind of job but the aluminium body immediately limits how heavy duty a task they can handle, they are deceptively light. I have no complaints so far so as long as you spec your job accordingly you won't be disappointed, the pricing isn't stellar for the quality but it could be worse.