K1 Max lubrication/cleaning schedule

Sirs.

I am noticing what appears to be an excessive buildup of “toner” on the x-axis of my K1 Max. I have a few questions in regards to this:

  1. What is this “toner”, and where does it come from?
  2. What is the cleaning schedule for the x-axis? I am having to clean the x-axis rod after every 1-2 prints. Is this normal? The y-axis rarely needs cleaning.
  3. What kind of lubricant is recommended for the x-axis? I have tried:
    a) PTFE (teflon)
    b) Medium weight silicone oil.

Any insight or answers to any of these questions is greatly appreciated.

Thanks,
The Kapt