Prusa Core One - Nozzle Wiper Remix - With steel brush and new purge bin

Index of changes

To help you and me keep track of things, I have added a short and informative list of my changes.

09.02.2026

• Following @kermit's last comment, I have now uploaded a text file containing the complete G-code to the download area.

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27.01.2026

• Modification of the upper part / brush cover uploaded (comment by @Marcin K)

• STEP, 3MF, and GCODE files uploaded for the modified cover

• STL files uploaded

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26.01.2026

• Added instructions describing how to attach the top cover (nozzle_wiper_remix_with_metal_brush_OT.step)

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22.01.2026

• GCode explained

• Link to stainless steel brush added

• Added note regarding brass nozzle

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21.01.2026

• Modified start G-code V1.00 uploaded

• STEP Files V1.00 uploaded

• 3MF File V1.00 uploaded

• BGCODE File V1.00 uploaded

• Video uploaded

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PLEASE READ FIRST

Brass Nozzle

The stainless steel brush used in the video is not suitable for brass nozzles. My video shows a brass nozzle — this was only a demonstration of the modified start GCode.

My modification will ultimately receive a hardened nozzle.

Disclaimer

I accept no liability for damage caused by using the G-code. The G-code has been shortened, simplified, and the order changed in some places. I can confirm that it works perfectly on a Prusa Core One with my Remix Nozzle Wiper with metal brush.

Credit

I would like to thank @6d6178 for his excellent preparatory work. The presentation, the documentation, and also the compilation of the G-code on the separate website are incredibly well done.

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Background

What always bothered me about the Prusa XL and now also the Prusa Core One was that you always have to clean the dirty nozzle manually before you can start printing.

In this remix, I have completed my initial preparations to use hardened nozzles for technical filaments. The steel brush is significantly more effective than a silicone wiper.

The start code has been adjusted so that the nozzle is cleaned before printing and before MBL.

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Assembly Instructions

I would like to emphasize once again that the use of stainless steel brushes is at your own risk. This Nozzle Wiper Remix with the wire brush is a purely experimental component. A silicone scraper or similar wiper is recommended!

Prepare assembly tools

First, you need to cut a strip of paper or cardboard approximately 8 cm long that fits through the opening.

Then fold the strip in half once.

Cut off both corners at the fold to make it easier to put on the top cover.

Installation top cover

The upper cover is easier to assemble with the folded cardboard strip than without it. However, caution is advised—the wire bristles are sharp and you could injure yourself.

Place the cardboard strip over the brush. All bristles should be covered by the strip.

Now place the top cover over the opening on the cardboard strip and slowly press down. Make sure that none of the brush bristles are blocking the way.

Remove assembly tools

Finally, either screw in the two countersunk screws first and then remove the paper strip, or hold the top cover in place and pull the paper strip upwards.

Video of the function

I created a first video of the remix with the modified start G-code V1.00

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Modified Start G-Code 

To ensure that the remix with the metal brush works, I have slightly adjusted the start code from @6d6178. The purge container next to the wire brush is used to heat up the nozzle and also to purge it before printing.  

ATTENTION:

The startcode of this website cannot be adopted one-to-one. The positioning of the wiping surface is not compatible and the GCode had to be corrected in this remix.

My modified GCode contains the following logic:

Start Sequence

Update 09.02.2026 - The start G-code has been revised! You can find the new version 1.01 in my files! Each change is commented on and described.

The start sequence has been designed to work optimally with PETG (Bambu Lab, Prusa, Material4Print, Polymaker) . The nozzle can simply remain dirty after printing because the start GCode cleans the nozzle again during the next print.

Prusa Core One - Modified Start G-Code V1.01

• Preheat nozzle to 175 degrees (default setting for PETG) - No “if” instructions yet!

  • In order to clean the nozzle, it must first be heated so that the filament on the nozzle softens.

  • In the following GCode versions, an “if” statement will follow at this point to automate the “start” temperatures of the individual filaments.

• Preheat the pressure bed to the “first layer” temperature - wait until heated up

  • The bed must be heated for MBL (default setting PETG) - Here, the temperature stored in the “first layer” in the slicer was used.

  • In the following GCode versions, an “if” statement will follow at this point to enable “Absorb Heat” for various filaments.

• Homing of all axes

• Search for printing plate

• Clean the nozzle

  • This part "Cleaning the nozzle before MBL" is very important.

  • The wire brush replaces the “nozzle cleaning” built into the Prusa print bed!

  • Here, the lines can be repeated as often as needed.

  • Increase speed by changing the number: Instead of “F5000,” you can also type “F8000.”

    • G0 X205 Y-16 Z1.00 F5000

      G0 X165 Y-18 Z1.00 F5000

      G0 X205 Y-16 Z1.00 F5000

      G0 X165 Y-18 Z1.00 F5000

      G0 X205 Y-16 Z1.00 F5000

  • Move the brush closer to the nozzle

    • G0 X165 Y-18 Z0.50 F5000

      G0 X205 Y-16 Z0.50 F5000

      G0 X165 Y-18 Z0.50 F5000

      G0 Z2 F1000 ; z-lift

• Run MBL

  • Once the nozzle has been cleaned mechanically, the MBL can be performed.

• Move to position above the purge bin

  • The nozzle heating phase takes place outside the pressure bed above the pruge bin

    • G1 X140 Y-17 Z2.00 F4800

• Heat nozzle to “first layer” temperature and wait until reached

  • M109 S{first_layer_temperature[0]}

• Purge filament into the bin

  • I deliberately changed the purging to the container in order to keep the area on the print bed free.

  • The advantage is that you can quickly print several prints in succession without removing the purge line from the print bed.

  • The amount of filament extruded is controlled by the command “E30.” 30 stands for 30 millimeters of filament.

  • With E10, only 10 millimeters are extruded.

    • G0 E30 F800 ; purge

• Wipe off filament from the brush

  • These lines can be modified and increased as desired.

    • G0 X165 Y-18 Z0.50 F8000

      G0 X205 Y-16 Z0.50 F3000

      G0 Z2 F1000 ; z-lift

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Test Setting - BETA!!!!

• The GCode entry “G1 E-0,20 F2500 ; retraction” has been moved to this position in the start GCode for testing purposes only, in order to prevent filament from flowing.

• The option to turn off the heatsink fan has also been removed. I would like to know if this has any disadvantages in terms of MBL.

• The “Absorb Heat” command has also been removed. This is sufficient for the PETG preset for now.

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Required materials

To use the Nozzle Wiper Remix, you need a few more things:

• M3 threaded inserts for welding (3x)

• Cylinder head screw M3 x 10mm (1x)

• Countersunk screws M3 x 8mm (2x)

• Metal wire brush (stainless steel) (1x)

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Necessary preparatory work

• The printed parts should be printed from a filament that can withstand heat without warping. In my remix, I used Prusament PC Blend CF.

• The handle of the stainless steel brush must be sawed off so that the brush head fits into the recess of the printed base. (The dimensions have been created/designed specifically for this wire brush.)

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What next?

In the next version of the Nozzle Wiper Remix, I will make the following changes, which I noticed while building the first version.

• Add a scraper roller between the purge container and the wire brush to prevent filament from being dragged along after purging. (... like in the Bambu Lab X1C.)

• The printed parts will be adjusted so that no supports are needed.

• The purge container can be mounted separately from the rest of the nozzle wiper.

In this remix, the silicone mat was replaced with a stainless steel brush. In addition, a small container was added to purge the filament.