Incorrectly loading or unloading filament can cause frustration, confusion, and, sometimes, severe damage to the MOD-t. The processes themselves are very simple, but it’s normal to encounter issues from time to time. Follow the step-by-step guides below to learn how to properly load and unload filament, switch filaments mid-print, and solve most load and unload issues!

How To Load Filament

1) Begin by removing the filament guide tube from the extruder input hole on top of the carriage.

2) Feed the filament through the filament entry port on the rear side of the MOD-t. (It’s to the left of the spool holder when you look at it from the back!)

3) Push the filament through the guide tube until it is protruding from the end of the guide tube approximately two to three inches.

4) Check that the end of the filament is freshly cut. Clip off any filament that is damaged, bent, has hashing, or is frayed.

5) Initiate the filament load process through the Print Queue Dashboard at the New Matter Store or the MOD-t desktop app and wait for the hot end to head up. When prompted to load the filament, feed the filament into the extruder input at the top of the carriage.

load filament
Click the Load Filament option of your Print Queue dashboard to initiate load.

6) Press the filament down by hand until the MOD-t tugs at the filament. It will then slowly feed the filament in by itself. (It may require more force than you’d expect, but by no means should you use excessive force on your MOD-t! Just a little push.)

7) Once the printer has pulled in the filament, press the filament guide tube back into the extruder input. Make sure it’s really in there!

8) When your MOD-t starts extruding spaghetti-like pieces of filament, firmly press the flashing front button.

How To Unload Filament

1) Begin by removing the filament guide tube from the extruder input hole on top of the carriage.

2) Initiate the filament unload process through the Print Queue Dashboard at the New Matter Store or the MOD-t Utility App and wait for the hot end to head up.

Click the Unload Filament option of your Print Queue dashboard to initiate an unload.

3). Wait. The printer will push the filament out of the carriage on it’s own.When the filament is completely out of the printer, clip the melted or frayed end of the filament and wind the filament back onto the spool.

How To Change Filament Mid-Print

Two-tone prints are so snazzy.
Two-tone prints are so snazzy.

You’ll need to change filament mid-print if you experience a filament snap or if you want to create a two-tone (or more!) print.

In the event of a filament snap outside of the MOD-t (i.e.: between the spool and the filament entry port at the rear of the MOD-t), your MOD-t will sense the snap and will pause your print to allow you to unload and load filament.

The front button will rapidly flash when a print is paused, either by the user or as a result of a filament snap.

If you have a filament snap past the filament sensor, hit the front button of your MOD-t and pause your print as soon as possible. If the snapped filament makes its way into the hot end, it will be difficult to retrieve via filament load or unload. Or, your printer could ghost print. Major bummer.

To create a two-tone print, pause your print at the point at which you’d like to swap filament colors. As we mentioned in the filament snap scenario, you can pause your print by firmly pushing the front button of your MOD-t once. (Note: You can also pause your print through the store by clicking the large Pause button on your printer page!)


  1. Remove the clear cover and access your MOD-t  through the desktop app (with a USB cord) or the store.
  3. Select “Unload Filament.”
  4. Follow the steps in the Unload Filament section above.
  5. Prepare your secondary color of filament or a fresh piece of filament. Make sure the end of the new filament is not frayed or damaged.
  6. Use a piece of paper to cover and protect your print from excess filament.
  7. Access your MOD-t through the desktop app (with a USB cord) or the store.
  8. Select “Load Filament”.
  9. Follow the steps in the Load Filament section above.
  10. Remove the piece of paper and put the clear cover on your MOD-t. Your print will resume.


If you’re having issues unloading and loading…

  • First check the position of your MOD-t’s carriage. If it is too high or low on the Z-axis, your printer will not allow loading and unloading. Your carriage should be about half an inch to one inch below the top of the Z-axis rod for a filament load or unload.
    • You can raise or lower the carriage using the gear at the back of the carriage. You can rotate the gear to the right to lower the carriage and to the left to raise the carriage. Only use your finger to turn the gear! If you use a tool, you could cause irreparable damage to the gear.


  • Restart the Load Filament or Unload Filament process. Check that the hot end is heating up by  placing your fingers near, BUT NOT ON, the hot end. If it never heats up, call Customer Support.

If your MOD-t won’t “Grab” the filament during a filament load…

  • Remove the filament from the extruder input and clip the end. It should be free of frays, hash markings, and melted ends. Restart the Load Filament process.

If your MOD-t says it has completed a filament unload, but there is still filament in the MOD-t…

  • Restart the Unload Filament process and gently tug at the filament to help release it from the carriage.

(Note: If none of these steps work for you, please call Customer Support for a more complete diagnostic test and troubleshooting experience.)

What NOT to Do!

1) Under NO circumstances should you ever insert anything other than filament into the extruder input at the top of the carriage. This includes, but is not limited to: toothpicks, drill bits, screwdrivers, fingers, Q-tips, beluga whales, pliers, tweezers, Twizzlers, and existential crises. These are all too large for the machine and will cause irreparable damage.

Adorable, but way too large for the extruder input!

2) When unloading, do not rip the filament out of the carriage. The filament will soften when the hot end heats up and should retract on its own. Yanking the filament out can strip the hot end of its Teflon lining. This damage can only be fixed by replacing your hot end.

3) Do not stop your MOD-t from completing a load or unload and then attempt to restart a load or unload. This will cause filament jams that, when serious enough, can permanently damage your MOD-t.

4) Make sure you NEVER load ABS or improperly sized filament into the MOD-t. The MOD-t uses non-proprietary 1.75mm PLA filament, so you have endless options of colors and styles, but it does not accept ABS filament or thicker PLA filaments.

5) Do not light your MOD-t on fire. This isn’t related to filament loading, but we thought we’d state the obvious here. This will most definitely void your warranty.



  1. Daniel

    I NEVER use the unload feature. it is much easier to just cut the existing line just above the unit and do a LOAD. let it get pulled through and then load the new line. I would remove the unload feature and combine both for a 100% success rate.

  2. Phil

    I agree with Daniel..

  3. Paul Betz

    The unloading portion of this article is no longer reverent as the unload button has been removed. I actually prefer the unload feature as I change colors a lot and the filament that is extruded will eventually add up to a lot of waste.

    • Paul Betz

      Edit to my previous comment: The unload button was removed from the web interface but is still available on desktop utility app.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>