If you plan on replacing the bearings only, you'll need the exact same bearings. Otherwise, you'll need to replace the rails and bearings.
Hiwin is one popular brand used by a lot of members here.
Gerry
UCCNC 2017 Screenset
http://www.thecncwoodworker.com/2017.html
Mach3 2010 Screenset
http://www.thecncwoodworker.com/2010.html
JointCAM - CNC Dovetails & Box Joints
http://www.g-forcecnc.com/jointcam.html
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
AND, in the model id MSA 30s-n what do the letters MSA stand for and what does the suffix s-n indicate?
try replacing the balls and the end seals.
If you are going to run the machine with no dust collection, you need to grease the bearings every 2-3 hours of run time, to keep the dust from getting in.
Gerry
UCCNC 2017 Screenset
http://www.thecncwoodworker.com/2017.html
Mach3 2010 Screenset
http://www.thecncwoodworker.com/2010.html
JointCAM - CNC Dovetails & Box Joints
http://www.g-forcecnc.com/jointcam.html
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
There's a harbor freight 25% off coming up for easter. Get some type of dust collection going and very carefully open and clean those bearings.
Thanks guys. The type of carving I do sort of precludes anything but a very expensive collection system. I make wood helmets and going 6 and 7 inches deep into the block just makes it tough to get the collector in there at the same time as the machine is carving. Also, it sounds like it might be possible to simply clean and re use the bearings? Is that true?
yes absolutely. unscrew the end seals and the balls fall out, wash everything and grease it. you will need a small amount of grease in the end seals so that the balls stay in while you screw it back on. measure the balls, you may find they are .001" smaller than a nominal size.. then buy some new ones if that's the case.
Thanks so much for the info. Where do I get the correct balls? Is there a particular grade or type or?? I already, without having seen your link first, took the bearings off and used my air compressor to "clean" them out. There was a little bit of shavings from wear. The bearings would not slide at all when I tried to pull them off the gantry rails by hand. Had to use the machine to push them off. After "cleaning" them and putting them back on they were not great but much much better. Then reattached and greased them up. Is it bad to use them this way for a little while or should I go ahead and do the rebuild you sent in the video?
my guess is they are completely clogged with sawdust. if you actually have metal shavings then you need new balls. first thing you need to do is measure them, you may be able to find the correct size on mcmaster carr. if not you can buy them from balltec
i would take them back off the machine and scrub them with a toothbrush and solvent if you don't want to pull the end seals off and wash the bearings out.
my guess is the return tube is clogged with sawdust and that is why they are so hard to move.
If the balls cannot circulate then that would accelerate wear significantly. Depending on the particular bearing system, the balls could be chrome steel or stainless steel. Same goes for the rails. The rails might also have a hard coating. It's usual for the balls and/or rails to wear more than the blocks. From your photo I can't see any evidence of rust which would be a killer, so a clean-out and reball might be all you need. Consider lubrication carefully - oil might be preferable to grease because dust is less likely to adhere to the rail and end up in the bearing. Assuming these rails and bearings are salvageable and you have the room, check to see if the double end-seal and/or metal scraper are available (and affordable) for extra protection. If you need to replace the system, buy one with those options. You should also look at covering the whole system with bellows.