Four Row Linear Bearing Rail

thingiverse

This is a 3D printed square rail linear bearing that utilizes four rows of standard .177 cal BB's as bearings. It is similar to the two groove bearing rail I have already published, but this rail has four rows of bearings instead of two. This allows for far greater load capabilities and heavier preloads as the balls are easier to recirculate with this design because each row is only making contact with the rail at one point. There is also less slop as the two rows on each side are trapping the rail. The rail is 200mm long, and there are four M4 mounting holes on the rail every 60mm. I designed some stops that fit into the mounting holes on the rail to retain the bearing on the rail, keeping the balls from falling out. Since I wanted this version to carry heavier loads, I did not include an adjustment for preload. Instead, I made three different versions of the carriages; light (zero preload), standard (.002" preload), and heavy (.004" preload). I'll post a video on my YouTube channel once I test their load capability, but it can handle my 185 lbs and still slide freely no problem. I wouldn't be surprised if it could handle 500-1000 lbs. I plan on finding out shortly. To assemble this bearing, you will need the following: * .177 cal BB's * M3 SHCS x 16mm long (4x) * M3 Nut (4x) You can watch an assembly video at https://youtu.be/cF8fXATjccQ. I also designed a 3D printer that uses these bearings, take a look at it here: https://youtu.be/XZXadrjIm_4