Any issue with using lube on the threaded z-axis rods?
In reading the threads on the forums there is much debate if one should lube the X/Y rods and bearings.
Can any harm be done by lubing the threaded z-axis rods?
Delrin, the plastic that is used for the z-nut that goes on the rods, has self-lubricating properties. I don't think adding any more lubrication will actually help performance. In my own opinion the only thing you do is introduce the possibility of attracting dust and dirt with the wet lubrication, and increasing wear.
The Prusa I3 Mk2 uses plastic to metal bearings on the Z axis rods. Other printers ie the Ultimaker 2+ have a metal to metal bearing on the Z axis and even include lube with the printer when you buy it. The issue as regards dust is within your environment. The plastic to metal Z axis bearings on the Prusa MK2 causes static charge and attracts dust. Lube will reduce it.
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