How To: Change the extruder nozzle

You may need to change your extruder nozzle from time to time, whether you're experimenting with your printing or your old nozzle is jammed up. Either way, we love to encourage people to develop their skills and make, break and fix their own things. If you’ve got the time and inclination, it may be worth trying to fix it yourself first!

Required equipment

• A pair of multi grips
• Tweezers or needle-nose pliers
• 7mm open spanner, ring spanner or socket wrench
• A replacement nozzle (0.2mm - 0.8mm)
• Heat-resistant gloves

Preparation

Have your new nozzle ready, turn on your Me2 and connect to BuildFlow or MatterControl. Home your printer and heat the nozzle to 180°C with the cooling fan turned on. Make sure to wear heat resistant gloves during this process as the nozzle and heater block must be hot to ensure an effective seal between the nozzle and filament feed tube.

Procedure

1. Raise extruder clear of the bed and extend X-axis forward to 180mm from home.
2. Further raise the extruder to a height that you can comfortably see and access the nozzle underneath.
3. Place a box underneath the X-axis to prop it up.
4. Apply multigrips carefully to the sides of the yellow heat block. Grip firmly, but be careful not to crush or rip the insulation.
5. With your 7mm spanner (or socket wrench), carefully turn the extruder nozzle anti-clockwise until it comes free. Be careful if using a spanner, you may need something to catch the hot nozzle with.
6. Place the loose tip on a heat resistant surface to cool down.
7. With the tweezers/needle nose pliers, screw the new extruder nozzle on a few turns to get it started.
8. Apply the multigrips again, as in step 4.
9. Using the spanner or socket wrench, turn the nozzle clockwise until it tightens against the end of the feedtube inside the heater block. Make sure that the nozzle has not tightened against the heater block itself, as this will result in a bad seal and possible leakage of molten plastic while printing!
10. Once everything is back together, you may carefully remove the box and return the extruder head to home. Turn off the heat and let the nozzle cool before turning off the fan.
11. Recalibrate your Z-Offset.
12. Make sure your print settings are appropriate for your new nozzle size. In particular:
1. Set the ‘nozzle diameter’ setting to match your new nozzle. “Settings & Controls” > “Settings” > “Printer” > “Extruder” > “Nozzle Diameter”
2. Reduce maximum print speeds with smaller nozzle size. You can increase speed with larger diameter nozzles, but may lose print quality.
3. You may need to decrease your acceleration speeds with nozzle sizes smaller than 0.4 mm.  “Settings & Controls” > “Settings” > “General” > “Speed”
4. You may need to increase print temperatures of your preferred filament by 5-10°C if using a nozzle smaller than 0.4mm. Likewise, you may need to decrease your print temperature by 5-10°C if going to a larger nozzle size (down to a limit of 200°C for most PLA grades)