ENG Rear Z Nozzle Brush Mount (A1 Brush) — Centered & Support-Free Remix

This is a remix of Caoimhe's ENG Rear Z DIY Nozzle Brush Mount, reworked to hold a Bambu A1-style silicone wiper brush as a nozzle wiper. It uses 2 M3x6 screws and mounts to the rear Z axis arm. Fits snug to the bed if using the stock Ender bed.

Two versions are included:

• Centered — brush trough is centered over the body. Cleaner look but the shelf overhangs, so this one needs support.

• Offset — trough is shifted with a chamfered underside so it prints support-free. Functionally identical, just easier/faster to print.

ASA or ABS recommended — this part sits next to the nozzle and a heated bed, so a heat-resistant material holds up far better than PLA, which can soften and creep there over time. PETG works too.

Print either version based on your setup — pick the offset one to skip supports, or the centered one if you prefer that geometry.

Klipper nozzle-wipe macro

This macro auto-homes if needed, heats to 200 °C if the nozzle is cold, then scrubs the nozzle across the brush in three sweeps. Add it to your config and RESTART. The coordinates near the top are for my setup — you must set your own (see "Finding your coordinates" below):

[gcode_macro CLEAN_NOZZLE]
gcode:
    {% if "xyz" not in printer.toolhead.homed_axes %}
        RESPOND MSG="CLEAN_NOZZLE: not homed, homing first..."
        G28
    {% endif %}
    {% if printer.extruder.temperature < 170 %}
        RESPOND MSG="CLEAN_NOZZLE: nozzle cold, heating to 200C..."
        M109 S200
    {% endif %}
    {% set saved_accel = printer.toolhead.max_accel %}
    {% set x_start = 108 %}
    {% set x_end = 136 %}
    {% set y_min = 236 %}
    {% set y_max = 242 %}
    {% set wipe_z = 5 %}
    {% set x_step = 2 %}
    {% set passes = ((x_end - x_start) / x_step)|int %}
    SET_VELOCITY_LIMIT ACCEL=5000
    G90
    RESPOND MSG="Cleaning nozzle..."
    G1 Z7 F3000
    G1 X{x_start} Y{y_min} F9000
    G1 Z{wipe_z} F1500
    {% for p in range(3) %}
        {% for i in range(passes + 1) %}
            {% set x = x_start + (i * x_step) %}
            {% if i % 2 == 0 %}
                G1 X{x} Y{y_min} F9000
                G1 Y{y_max} F6000
            {% else %}
                G1 X{x} Y{y_max} F9000
                G1 Y{y_min} F6000
            {% endif %}
        {% endfor %}
    {% endfor %}
    G1 Z7 F3000
    SET_VELOCITY_LIMIT ACCEL={saved_accel}
    RESPOND MSG="Nozzle clean complete"

Run it by sending CLEAN_NOZZLE, or call it from your PRINT_START / PRINT_END.

Finding your coordinates

Edit the six values at the top of the macro to match where your brush sits:

1. Install the mount, seat the brush, and G28 to home.

2. In Mainsail/Fluidd, raise Z to ~10 mm so you can't crash anything, then jog the nozzle to one edge of the bristles. That X/Y is your x_start and y_min.

3. Jog across to the far edge of the bristles in X — that's x_end. Jog front-to-back across the brush depth in Y — those two values are y_min and y_max.

4. For the first test, set wipe_z a few mm high so the nozzle hovers above the brush, and run CLEAN_NOZZLE. Confirm the path tracks over the bristles. Be ready to hit emergency stop.

5. Lower wipe_z a little at a time and re-run until the nozzle tip digs lightly into the bristles. The brush should sit slightly proud of nozzle height so there's real contact.

Note this macro auto-heats to 200 °C, so the nozzle will be hot on every run — do your hover test first so a mis-set coordinate doesn't drag a hot nozzle into the mount. Coordinates will differ between the centered and offset versions, so re-measure if you switch.

Credit to Caoimhe for the original mount, and to citr0net's E3NG config for the macro structure.