Linear Rail lubrication and maintenance

With Carbide now supporting the HDZ with linear rails and more people adding them to the X axis I think it’s a good time to start talking about care and maintenance.

Dry and dirty bearings will cause rough movements and can effect your cut performance. Most of what I’ve read says to use a lithium grease and lube when you wipe your rail with a cloth and its dry.

During the lube process I’ll run the axis through its whole range of motion over and over while continuing to wipe the rails until they are clean. Basically lubing until the contaminates are flushed from the blocks.

What do you guys do?

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I do not have an HDZ but do have a Shark. I use Super Lube Dri-Film Lubricant. The lubricant is dry and does not attract dust and dirt. It is slightly moist when sprayed but evaporates the carrier and becomes dry with a white teflon mist left behind. I have never had any trouble with the linear rails being dirty. Occasionally I clean the faces of the bearings because they tend to collect dust over time.

Thanks for the reply!
What type of bearings are on the shark? Most of the research I’ve seen seems to say to not use any type of dry lubricant (PTFE powder, graphite powder, etc.) with any recirculating ball or roller type of bearing. While these lubricants are good for sliding motion, they do very little to aid rolling friction.

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The dry lube does not attract dust like petroleum based lubes. The rails are a sliding friction but I agree that the acme screws/balls may not benefit from the dry lube but I dont think it hurts them. So one train of thought is to just wipe them down and let them wear and replace them periodically. Another thought train is to lube the rails and acme screws/balls with a lube. Since any type of wet lube will attract dust and make it cling to it the best may be some type of dry lube. In the end you just try some things based on experience and your best knowledge and change as things do not seem to work. I do not think that the dry PTFE lube is a long term detriment to my equipment and better than leaving it dry. Remember the rails are steel and I have a very humid environment in East Texas so a protective coat is better than no coating.

Check out the following about the Super Lube Dri-Lubricant:

https://www.super-lube.com/multi-purpose-lubricant-with-syncolon-ptfe

FYI, I have seen your posts on your work and it is top notch.

There’s been some discussion of similar issues on the forum for Luke’s HDZero, which uses similar slides and ballscrews. I don’t think I’ve seen any official consensus on the best maintenance routine.

Personally, I find HiWin’s maintenance suggestions for their linear slides and ballscrews to be worth following. The slides and screws that we’re using are largely clones of HiWin’s. Their guides make interesting reading anyway; among other things, they lay out the math for selecting the right ballscrew and explain how to calculate the resonant frequency for long ballscrews. Which explains why I can’t go faster than ~16,000 mm/min on my 1500 mm X axis without problems.

https://www.hiwin.com/pdf/linear_guideways.pdf

Hiwin doesn’t actually recommend a specific grease for linear slides. They say to use lithium grease before initial installation, and then to re-lubricate every 100 km. For high-speed slides (over 60m/min / 2300 ipm) they recommend oil, but say that it needs to be oiled much more frequently.

For ballscrews, their recommendations are more complicated but basically similar. These seem to be the two most important quotes:

To achieve the ballscrews’ maximum life, the use of antifriction bearing oil is recommended. Oil with graphite and MoS2 additives must not be used. The oil should be maintained over the balls and the balltracks.

HIWIN ballscrews require appropriate lubrication either by greasing or oiling. Antifriction bearing oil is
recommended for ballscrew oil lubrication. Lithium soap based grease is recommended for ballscrew greasing.

They give 100 km and/or 6 months as the recommended lubrication interval, but that depends on the use, load, temperature, environment, etc.

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I used to use a light machine oil, turns out the heavier stuff really dampens the movement in a good way. It didn’t cause any noticeable drag and was tested to 1000ipm.

Ballscrew gets the same squirt n wipe and runs great.

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Vince,

Are you taking the small screw off the face of the block and flushing oil/grease directly in there? Any updates on what is the best oil or grease to use? Looking to purchase some.

Yes I lube from the side ports. And actually have switched back to a lithium grease. Not sure I want to be quoted on what’s the best to use but we put so little force on them in our application, I’m not sure it matters a whole bunch.

Just keep them lubed and clean

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