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!
I’ve never had and issue with the linear rails rusting in all the years I’ve been 3D printing. But I do live in a drier temperate climate also. But dust will eat the seals up very quickly as well. If rust is a worrisome issue, hard chromed linear rods are also easily available to prevent any worry about rust. And they would outlast the the non-chrome rails significantly. That’s what I use.
As always YMMV