PDA

View Full Version : Mini Kossel - Low cost bearing alternative



asb_79
01-29-2014, 02:00 AM
Playing with some ideas for alternative bearing to the recommended Hiwin linear rails for the Kossel mini.

Here is what I have so far,

Used the carriages for the Graber dual V wheels, in place of the V wheels though, I've used two 623 bearings and an O-Ring with a 4mm section diameter. The carriage moves quite well, there is a little flex from the rubber o-rings but it doesn't look like it affects the vertical movement. I think it would benefit from a larger oring section but that will need a new carriage as the "wheels" will get bigger, I may design one when I get a chance.

I might build up a machine, or changeover the bearing in my Kossel to see how they work. The bearings and O-Rings cost me $22AUD

I've used in order of assembly, M3x35 screws (30 would be better), 2x M3 washers, 1 x M3 Nut, 623 bearing, M3 nut, M3 washer, 623 bearing, M3 Nylock. Hope that makes sense, with this combination the carriage is offset from the rail the same distance as if using a Hiwin rail.

Halfdone
04-01-2014, 09:40 PM
Nice Idea. I struggled trying to find a homebrew solution to "smoothly" running on the extruded aluminum (mine is painted and has a slightly rough texture). I would probably be concerned with the o-rings developing flat spots and getting sloppy. could you add spring loading to the effector to keep things tight as they wear?