I am curious how often do you service the linear rails on the 3D-printer:

  • How often do you lubricate them (MGN9 or MGN12)?
  • How do you lubricate them?
  • What volume of lube do you use?
Explanation of how often you should do it (HIWIN Lubricating instructions for linear guideways and ballscrews)

Most 3D-printer use MGN12. Reading the HIWIN documentation they shall be lubricated every 20-50km (depends on a lot of factors).

How much is 50km in print time? Assuming an average speed of 300mm/s that would be approx. 46 hours!

In other words, the generic MGN12H carriage needs 1-2 times per week maintenance.

How much lube is suggested (horizontal mounting)? 70µL for MGN12H. For MGN9H it is 30µL!

  • morbidcactus@lemmy.ca
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    6 months ago

    Generally lubricate every few hundred hours, however you really should consider condition based lubrication over time based, over lubrication is actually a really common failure mode for rotary bearings and would not be surprised if the same is true for linear bearings. 50km intervals sounds like an order of magnitude too frequently based on what I recall from Thompson, yeah the bearing type, loading, cleanliness etc all play a part, but their examples are in the hundred of km range, not tens.

    Are you ensuring that you’re actually getting grease into the bearing as well? The MGNxxX bearings are usually sealed, you need to get past them to actually lubricate as you want to expel the degraded grease. Myself, I do some white lithium via syringe and then machine oil on the rails, and even that’s probably excessive. Moving the bearings by hand along their length of travel will give you a feel for them as well, there’s a lot more you could do but I’ll be totally honest that it’s probably not worth doing, consequence of failure is basically nothing in the hobby space (no risk of injury, low costs, no impacts to business, basically if a bearing goes you’re out what like $50? and an hour)

    • EmilieEvans@lemmy.mlOP
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      5 months ago

      The 50km figure is out of the HiWin application note at 30% load capacity. Even with 0% load it won’t go above 150km.

      Looking at the Thompson-Link: It is for the self-lubrication block (long-term lubrication unit) which indeed has a much higher endurance. Raising maintenance intervals to roughly once per year. As far as I know, they are only available for MGN15 and larger.