Gantry mounted nozzle wiper for CoreOne

There are plenty of nozzle wipers for CoreOne. But most of them are attached to the bed. So you can only use them for the first (few) layers. This one is mounted on the front left Y-bar holder. So you can use it for any layer. 

It uses a Bambulab X1/P1S style silicon brush. You can get them cheap from aliexpress. Many others use a Bambulab A1 style. The reason is that I have a CoreOne+, and the printhead would hit the vent opener if it wiped wider than that on the left side.

I printed it in PETG with 0.4mm nozzle and 0.2mm layer height. But I don't think it's critical to use those exact sizes. It will need supports, but there's one edge that the support can't fix, so you will need to file it down/sand it.

This print clips on without any fasteners. But it can be a bit hard to reach the hooks if you want to remove it. There is a loop for a 3 mm Allen wrench to help unhook it. It can help when installing it also, but it's not necessary.

Cautions when mounting!

Make sure that the cable for the white LED strip is out of the way. It goes around the same corner where this is mounted. The USB cable for the 3DBuddy is also routed there, but it's less likely to be in the way.

It's rather tight in this corner, and the print head can come close to this print. It can't touch on my printer, but I don't know how big tolerances there can be between printers. The part I'm most worried about is if you have any cables routed in front of the lower thumb screw for the nozzle. They would need to be rerouted or they could be pinched. 

Some nozzles have different lengths which means that they dig down more or less into the brush. Too much difference means that this print won't work. That's for a possible future upgrade.

When you mount the print for the first time, disable motors and push the printhead by hand to check that nothing can hit.

Using the wiper

I've encountered some filament/STL combinations that would benefit from a wipe between each layer. In that case put the wipe in the "After layer change G-code".

Another time where it can be useful is after manual color changes if you don't want a prime tower. In that case there's a "Color Change G-code" section.

The custom G-codes can be accessed by setting PrusaSlicer in expert mode and go to Printer => Custom G-code.

Here's an example of a wipe script. It's not by perfect, and could probably benefit from a different pattern. But at least it's a starting point.

; Safe coordinates wrt vent opener.
; X <= 13 or X >= 34 or Y >= -8
; Safe coordinates wrt min corner:
; X >= -1 and Y >= -18
; G90 ; Should already be in absolute coordinates
; M83 ; Should already be in relative extrusion
G1 F1500 E-5 ; Retract
; Move to wiper without touching vent lever.
G0 Y0 Z{layer_z + 5} F5000
G0 X2.5
G0 Y-12
; Three ovals over the wiper.
G3 X2.5  Y-17 I1.5  J-2.5
G3 X11.5 Y-17 I4.5  J7
G3 X11.5 Y-12 I-1.5 J2.5
G3 X2.5  Y-12 I-4.5 J-7
G3 X2.5  Y-17 I1.5  J-2.5
G3 X11.5 Y-17 I4.5  J7
G3 X11.5 Y-12 I-1.5 J2.5
G3 X2.5  Y-12 I-4.5 J-7
G3 X2.5  Y-17 I1.5  J-2.5
G3 X11.5 Y-17 I4.5  J7
G3 X11.5 Y-12 I-1.5 J2.5
G3 X2.5  Y-12 I-4.5 J-7
; Move to point in front of vent lever.
G0 Y10
G0 X24
; Move back
G0 X{position[0]} Y{position[1]} 
G0 Z{position[2]}
G1 F1500 E5 ; Deretract

Further work

It would be nice to have a "wiper wiper" so the brush is clean next time.

Update the wiper script.

Support for A1 brush.

Adjustable height.

More testing.

Edit

I've learned that the most common brush on other designs are Bambulab A1 style, not two of the one I used.

Added caution on different length nozzles. (Thanks ovelux_213831)