Some people already know the problem. You fit your Nextruder nozzle and screw it on too tightly. This squeezes the tube at the attachment point, which can lead to faults and blockages.
According to Prusa, the fastening screw with maximum 0.7nm must be tightened. If you don't have a torque screwdriver, you could easily overtighten it. However, the screw should not be under-tightened either, as the entire hotend is held here and must not be allowed to slip, as this can of course also lead to printing errors.
However, it is relatively easy to remove the dent. To do this, you need a stainless steel rod with a diameter of 2mm. The rod should be approx. 10cm long. These are available cheaply on the Internet and are otherwise also good for model making.
First, the end of the stainless steel rod that is pushed into the Nextruder nozzle must be filed a little round.
Now place the stainless steel rod on the Nextruder nozzle as shown above. Now mark the point at the red arrow with a marker or a file.
Now simply insert the rod into the nozzle from behind. You can now use a small hammer to knock the rod in a little in order to bulge out the pinched area. Proceed with great care, as this could damage the heatbreak. Therefore, stick to the exact markings. The nozzle tip can also be damaged if handled incorrectly.
Then pull the rod out again using pliers. Repeat the process if necessary.
That was 🙂
PS: By the way, there is a good and variably adjustable Torque screwdriver from the Wiha company. This should have a setting range of 0.4-1.0nm.
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