Strings or Lumps On Outside of Part

Note: Legacy documentation is no longer being updated.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


This is caused by wet nylon. You will need to replace the nylon with a new, dry roll.

  1. Slightly wet nylon presents with small lumps on the outside of the part (like this yellow hexagon)

  2. Very wet nylon presents with stringing as seen on the circular reference part. 



We have provided a sample part below to help determine if your nylon has accumulated too much moisture. If your wrench and / or other reference part has excessive stringing, the change your nylon for a dry roll. 

Test Part Instructions:


You must have Nylon and Kevlar properly loaded in your Mark One to print the supplied Wrench test.

  1. Download the file Short_wrench_kevlar_test.mfp below.

    NOTE: you must download the file appropriate to your printer version
    Mark One Short Wrench Kevlar Test File
    Mark Two Short Wrench Kevlar Test File

  2. Copy file to USB flash drive (Do NOT use provided Recovery USB Drive). Learn more about printing from USB here ->.

  3. Insert the USB flash drive into the rear USB port

  4. One the Mark One screen, select the Menu Icon (upper right corner) 

  5. Select Print From USB

  6. Select the Short_wrench_kevlar_test.mfp

  7. Select Print. 

  8. If your final part has excessive stringing or large blobs of nylon, you will need to change your nylon spool for a new and dry one by following steps 9-12 below:

  9. Run the Unload Material routine and remove and discard the nylon in question.

  10. Open a new roll of nylon, paying close attention to the Material Handling and Storage instructions.

  11. Run the Load Material routine.

  12. Print away!