Adjust Fiber Prime Length

Note: Legacy documentation is no longer being updated. For up to date instructions, see our Desktop Series support articles.


While printing fiber the Mark One 'primes' the fiber nozzle by extruding fiber from the cut point (located at the opposite end of the fiber Bowden tube from the print head) to the nozzle. Prime length is sensitive to material diameter and machine to machine tolerance variations. The 'Adjust Fiber Prime Length' Advanced Utility allows you to fine tune this important parameter on a per fiber type basis.

To calibrate the Fiber Prime Length:

  1. Make sure you have fiber loaded into your machine and that it can feed through the nozzle.
  2. Make sure the print bed is clear and properly seated in the kinematic coupling.
  3. On the touch screen go to Settings > Utilities > Advanced Utilities > Adjust Fiber Prime Length
  4. Select which fiber material you currently have loaded
  5. Confirm that the material is properly loaded.
  6. Wait while your Mark One homes the printhead and bed. It will then extrude the default prime length.
  7. If the end of the fiber is not touching the print bed
    1. Use the buttons on the touch screen to raise (or lower) the print bed until the end of the fiber is just barely touching it.
    2. If the fiber coming out of the nozzle is curled use one hand to carefully straighten it down towards the bed, without pulling it farther out of the nozzle.
  8. If the fiber is making contact with the bed
    1. Move the bed down until the fiber just barely cannot reach the bed
    2. Move the bed up once so the fiber is barely touching the bed
  9. If the end of the fiber does not appear out of the nozzle:
    1. Make sure nothing is obstructing the fiber in the fiber bowden tube.
    2. Finish the utility, clear the fiber and try again.
    3. If none of the above work please contact support for assistance.
  10. Once the bed is barely touching the end of the fiber click Save.
  11. Carefully pull the fiber out of the nozzle. Be sure to pull it straight down and out to avoid breaking the fiber inside the nozzle / bowden tube.
  12. Inspect the bowden tube to make sure no fiber is left behind.
  13. Select Done when the fiber bowden tube is cleared. 
  14. You're Done! You can check on the prime values for your machine by going to Settings > Printer Info > More