Nozzles

Tungsten Carbide Nozzle

Purge your nozzle

INFO

This is an optional operation.

Removing the filament left inside your nozzle will reduce the risk of sticking polymer on your threads. The method used here is called “Cold Pull”. Basically, you manually insert fresh filament inside your hotend, and quickly remove it before it melts. You need to let it soften. By repeating this step, you will purge any filament left and clean your nozzle at the same time.

You don’t need to use a specific type of filament for this step. We use the exact same filament type present inside the hotend with great success.

1. Preheat your nozzle to the last filament you have used

2. Disengage your extruder driving mechanism for easy manipulation

3. Insert a filament inside the extrusion system

4. Pull it out quickly, as soon as you feel it soften

5. Cut the soften part

6. Repeat steps 3 to 5 until there is no more polymer inside your nozzle. You will recognize the nozzle shape on your soften filament once you reach this point.

Remove your current nozzle

1. Heat the nozzle up to your previous printing temperature

2. Make sure you follow a guide made for your printer or hotend before applying any force to your nozzle.

   Parts can be broken very easily. Each hotend has its technique where the heat block needs to be held in a certain way.

3. Remove the current nozzle

Install your Tungsten Carbide nozzle

1. Make sure your hotend is still hot.

   It should be at the previous printing temperature or higher, depending on what you will print.

2. Carefully position the new nozzle and tighten it by hand.

   It is suggested to use a socket to avoid any burning risks.

3. This step is required if your heat break has threads inside the heat block (most M6 variations).

   Once you are unable to tighten it by hand, check if the threads are still visible. If the hex’s flat section is touching the heat block, you’ll need to tighten the heat break deeper inside the heat block. Loosen the nozzle, tighten the heat break and check again.

   WARNING

   Example of a bad installation

   

   Nozzle is touching the heatblock

   

   Heat break threads are still visible

   GOOD

   Example of a good installation

   

   Nozzle and heat block correct spacing

   

   Heat break deeper inside heat block

4. Tighten the nozzle using a torque wrench. Different nozzles and filaments material combination might require a different amount of torque.

   A good start is around 0.5Nm. Based on the temperature, refer to the table below for the maximum amount of torque you can apply. Always use a tool with 6 faces when tightening. An open wrench shouldn’t be used and can permanently damage the flat faces.

   T (°C)	M6-1.75mm	M6-3.00mm	M6-3.00mm HF	M7 MK10	M10	UM3
   25	6.8	6.1	6.1	9.7	40.7	6.7
   200	5.6	4.9	4.9	7.9	33.0	5.5
   300	4.8	4.2	4.2	6.8	28.5	4.7
   400	4.0	3.6	3.6	5.7	23.9	3.9

5. Check your Z height

   Do not home your printer. Slowly move the Z axis down and check with a thickness gauge. Adjust your printer to the new Z height.

6. Adjust the temperature and flow

   The tungsten carbide nozzle will print at a much lower temperature than other nozzles due to its high thermal conductivity and optimized flow geometry. If you keep the same settings as before, make sure to run a single wall test and adjust the flow.

   1. Slice a square part with a single wall, without any infill, top layers, and bottom layers.

      Note down the line width specified by the slicer. Make sure the part is big enough to let the material cool down before another layer is laid down. A 40mm square by 10mm height should be a minimum

   2. Measure the line width. Adjust the flow for your next prints.

      Note that speed and temperature will change the flow behavior, run this test at a similar setting you will later be printing.

Miscellaneous

Change a nozzle with a Prusa i3 Mk3

Here's a general video on how to change a nozzle on Prusa i3 Mk3

Change an Ultimaker 3 nozzle

Here's a general video on how to change a nozzle on Ultimaker 3