Some people may already be familiar with this problem. You mount your Nextruder nozzle and screw it on a bit too tightly. This squashes the tube at the attachment point, which can lead to errors and blockages.

According to Prusa, the fastening screw can be tightened to a maximum of 0.2-0.3nm. If you don’t have a torque screwdriver, you risk overtightening. However, the screw shouldn’t be tightened too loosely, as it holds the entire hotend and must not slip, as this can naturally lead to printing errors.

I’ve developed a fully 3D-printable torque wrench for the Nextruder. This makes it easy to set the correct tightness.

https://www.printables.com/model/1251975-torquey-nextruder-edition-torque-wrench-for-prusa

However, the squash can be relatively easily removed. To do this, you need a stainless steel rod with a diameter of 2 mm. The rod should be about 10 cm long. These can be found cheaply online and are also useful for model making.

First, the stainless steel rod at the end that goes into the Nextruder nozzle needs to be filed slightly round.

Now place the stainless steel rod on the Nextruder nozzle as shown above. Mark the spot by the red arrow with a marker or file.

Now simply insert the rod into the nozzle from behind. You can then tap the rod in slightly with a small hammer to flatten the dented area. Proceed with extreme caution, as this could damage the heatbreak. Therefore, follow the exact markings. The nozzle tip can also be damaged if handled improperly.

Then pull the rod out again with pliers. Repeat the process if necessary.

That’s it 🙂

PS: There’s a good, adjustable torque screwdriver from Wiha. This should have a setting range of 0.1–0.6 nm.