I waited a little while to see if any experts provided a definitive reference. This list amazes me at times with the cumulative knowledge, and I'm still hoping something is posted that is concise and informative. I know that Misumi provides good technical info for their products and I seem to recall them discussing the maintenance and lubrication of linear motion systems. Found it!
http://blog.misumiusa.com/ball-screw-lubrication-tips-application-grease-vs-oil My simplistic approach: 1) If the manufacturer of the machine or the linear motion components recommends a specific lubricant, that's what I use. Even the expensive grease is cheap considering that a little goes a long way and replacing motion control components is very expensive and time consuming. 2) Each machine has its own grease gun, etc., stored at the machine. I consider this part of the machine. I don't want to wonder what grease each machine needs, and I don't want to go looking for the right grease. If it's right there, I'll do the proper maintenance. 3) Barring a manufacturer's lubricant specification, I choose a good synthetic grease. It's usually a Mobil product. I prefer greases that are reddish or cream colored, rather than black or dark brown greases. I want to see a thin film of grease, but when I wipe off the old grease I don't want to see black gunk on the light blue lint free shop towel. If I see black, I assume it's some grimy contaminate. There is a very cursory introduction to grease on McMaster-Carr's site. http://www.mcmaster.com/#standard-grease/=124w94o Click the About Grease link. Grease is basically oil and a thickening agent. I select a synthetic oil base because it doesn't form gummy or varnish residues as readily as petroleum based oils. Similarly, I look for a thickening agent that doesn't readily oxidize to form thick gummy residues. The thickener oxidation resistance is one of the columns on the McMaster-Carr About Grease information page. I would prefer a thicker grease because the thinner greases will often separate in the grease gun and leak oil all over the place and make a mess, but I don't let that determine my choice of NLGI ratings. Instead, I choose the thickness based on the application and temperature, and I keep the grease gun (usually the small 3 ounce size) in a heavy duty plastic zip top bag. Probably more important than the grease in my opinion is the lubrication schedule and overall cleanliness. I'm a bit of a stickler about this. Cover the motion control components if they're exposed to contaminates, but don't cover them and forget about them. Precision motion control components require maintenance. I prefer to wipe the old grease off linear rods or linear rail at the end of the day. Wipe away from the bearings using a clean lint free shop towel. Inspect the wipers for damage and replace if needed. Use a grease gun to inject new grease into the bearings to push out the old grease. Run G code that moves the machine to the limits to distribute new grease to the linear rods or rails. It's a good idea to run this program at the start of the next day to exercise the machine before the start of the next day's machining. Finally, when we build machines, we have the opportunity to improve the motion control longevity by keeping these parts clean, and this concept applies even on the simplest machine. I'm currently wrapping up a 24" X 24" CNC router build, to be used almost exclusively to cut plastic sheets. The Y axis linear rods are exposed on the side. Rather than a simple spoil board on top, I'm using a 1/2" thick ABS plastic top plate that overhangs the sides as much as possible to protect the linear rails from swarf dropping onto them. The top plate has side shields that extend upward to almost completely eliminate swarf dropping onto the Y axis linear rods. An air blow off will constantly push the chips toward the back as they're produced. The top plate extends far enough to the rear to protect the Y axis stepper motor and the Y axis ball screw. The top plate has a vertical back wall to stop the chips from falling off the back of the machine. The chips pile up on the shelf behind the active machining area, where they can be easily vacuumed away. Even though the Y axis linear rods are well protected from chips and debris, they are easy to access for quick daily maintenance. On 4/25/2016 9:17 AM, Nicklas Karlsson wrote: > Do anyone have experience on lubrication of slide bearings, ball bearings and > such things? ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
