nozzle wipe

mwolter

Wire brushes wear down the nozzle and the bristles bend and become less effective. I like your idea on using the dish cscribber though, just concerned it would take a good amount of space.

Working on a design that uses the silicone blade from a squeege (used to wipe water off windows). Got this idea from @deckingman.

Properly supported it should clean the nozzle well, filament debris should not build up and stick to the blade (filament doesn’t stick well to silicone), it should not wear the nozzle, takes little space and it should retain shape.

Added to the print start gcode will be a macro that zig zags across it a few times.

jens55

Somehow I don't think a wire brush is a good idea unless you have a hardened nozzle. I suspect the brass used in brass brushes is also of a harder alloy then a standard brass nozzle and I would think that you would see some wear depending on how often you wipe.
The thing that would concern me most is the wires of the brush interacting with the inside edge of the nozzle. I can see that edge getting rounded and then affecting the clean and precise flow of the extruded plastic.
I could see a combination of two cleaning surfaces - occasional brass brush but normal cleaning done by silicone

zapta

Here is an example of a professional one

https://store.stratasys.com/stratasysstorefront/stratasys/en/Materials-%26-Service-Consumables/NA/Flavors/540-00200/p/540-00200

Edit: and here is a video by DPT
https://www.youtube.com/watch?v=PhiDD0E_Fjg

arhi

@zapta said in nozzle wipe:

The examples of nozzle wipes I saw were metal brushes, more like this https://www.aliexpress.com/item/32918753824.html

I'm using brass brash when cleaning by hand. Issue I have with brass brush is with these new X nozzles from E3D that come with some plastic-fobic coating .. no clue how hard that thing is and if wires will scrub it .. also, brushes shed and those bristles are nasty buggers when they enter cloathing, or skin, or god-forbid your electronics so I never use metal brushes for "automatic" cleanup.

What automatic cleaning needs to deal with is some oozing and that's about it, the silicone should be more than adequate. Normally one would use few mm thick strip of silicone and just go over it few times, problem is I don't have a stripe of silicone (if you look at my wiper, it's designed to hold a stripe of silicone ) so I'm trying this kitchen appliance

arhi

@mrehorstdmd said in nozzle wipe:

I attempted to clean the nozzle using a wire brush and didn't have much success. I didn't mess with it much after the initial attempt, so maybe it can be made to work. I was thinking maybe a combo of wire brush and silicone or teflon blade

I clean them regularly with brass brush by hand.

I would skip on the teflon (PTFE) blade as it's normally "too stiff" and does not work good over 230C (release neurotoxin fumes) and I want solution up to 320C so...

arhi

@mwolter said in nozzle wipe:

just concerned it would take a good amount of space.

I just cut it and am preparing to do tests in an hour or so (if work stuff don't get in the way) so I'll share my experience. It could be a total failure, I'm prepared for that

Working on a design that uses the silicone blade from a squeege (used to wipe water off windows). Got this idea from @deckingman.

Yes, I seen his silicone strip and it inspired me to make this wiper in the first place! This is not nearly stiff as his rig but worked for a while with the magnetic rubber instead of silicone blade. Still don't have silicone blade so testing this "sponge" :). Getting stuff during quaranteene is hard, especially as we have these 2-3-4 day lasting "police hours" where you can't even go out to take the garbage so I have to do with what I can find in drawers, kitchen, kids toys...

arhi

@zapta said in nozzle wipe:

Edit: and here is a video by DPT
https://www.youtube.com/watch?v=PhiDD0E_Fjg

he's using the same PRC made brass brush I use for cleaning stuff. It comes in a package of 4, 2 different stifness plastic ones, one brass and one steel brush. These brass brushes leave scratch marks on the brass nozzle and aluminium heater block so are not very soft. They do clean the nozzle awesomly but I would not use them on the tip, and especially not for every print.

deckingman

Saw my name mentioned a few times in this thread. For info, I tried a few other things before ending up with the final design which uses a slot milled into a piece of aluminium to hold and support the silicone strip. Things that don't work are simply fixing it at both ends. No matter how much tension is applied, nor how close you can get the strip to the nozzle, it simply pushes the silicone out of the way rather than passing over it. For additional information, I'm still using the original strip and haven't yet needed to replace it. But when used with a purge, my "bucket" is too shallow so occasionally, the nozzle will pick up some previously purged filament at the end of the wipe and drag this back over the silicone strip. I need to fix that.....

arhi

@deckingman said in nozzle wipe:

Things that don't work are simply fixing it at both ends.

Assumed so, that's why I designed that wiper to hold the silicone strip from both sides throughout the full length. Unfortunately do not have the silicone strip so could not test it out

The milled channel you use, do you think without milling the channel and just using 2 L shape alu profiles 5x5mm screwed in the bed and silicone strip between them would work?

using the original strip

Where did you get the strip from if I may ask?

deckingman

@arhi Anything that can clamp the silicone along one edge should work. You might be able glue it to a piece of something rigid. Not sure what would work - silicone adhesive maybe?
I honestly can't remember where I bought it from but it would likely be off eBay. I had to buy a 3 or 5 metre length but it wasn't expensive.

arhi

@deckingman cool, when this whole thing finish I'll try to get one strip that looks perfect

arhi

def. has potential but not ideal .. this .6 nozzle is rather leeky need to add some retraction to wipe procedure

https://youtu.be/ze0WUGS4cQ4

deckingman

@arhi That video is private so I can't view it. For info, and in case you haven't seen it, you can see mine here from about 1min 40 secs https://www.youtube.com/watch?v=IG3AGKDzdH4

arhi

@deckingman thanks, I clicked on public and did not click on done but save and ... well happens should be public now

Yes, I have seen that video, and that's what inspired me to do this wiper in the first place as cleaning nozzle manually before homing is not very efficient due to the position of the printer and since I installed .6 nozzle there if I don't clean it before homing it will have nasty Z offset

I normally have some type of nozzle cleaner on every printer but I can't say I'm satisfied with any of them :(. This type is not possible on them as, usually, head can't move outside of the printbed area so anything mounted outside of the bed won't work. Here I have few cm so I used them ... now just to make it work.

IMO this will work for now but as soon as I can I'll add a second 2020 along side Y axis to hold on to the proper silicone strip.

As for the glue, dunno, I think I'll go with mechanical option, silicone, ptfe, pp, hdpe are materials I never had luck gluing.

deckingman

@arhi Ref the YouTube videos - I discovered just the other day that you can also use "unlisted rather than "public". That way, they don't show up in your channel or any searches, but anyone with the link can view. Ref the "mechanical" option - if you had wide enough silicone, you could perhaps screw it to something flat, rather than sandwich it between two plates - might need some big washers. Just a thought........

jens55

If you have a U channel, why not use a couple of push pins in previously drilled holes near the top of the U channel as a mechanical fix to prevent the strip from being pushed out?

deckingman

@jens55 said in nozzle wipe:

If you have a U channel, why not use a couple of push pins in previously drilled holes near the top of the U channel as a mechanical fix to prevent the strip from being pushed out?

That should work. Although in my case, I milled a slot the right size so that the silicone stays put without the need

arhi

I modified a bit height of the wiper and the script and I'm super happy with the results

code that works
wipe.g

if !move.axes[0].homed || !move.axes[1].homed 
  echo "X and Y axes not homed, aborting the wipe"
  M99

if sensors.analog[1].lastReading < 200
  echo "Extruder too cold, no point wiping, aborting the wipe"
  M99

; Drop all motor currents down
M400
M913 X30 Y30 Z25

; relative extruder (if I understand how push/pop work in RRF 
; this should be returned to what it was on exit from this macro)
M83 

; Wipe
G0 X-110 Y40  F9000
G0 X-135 Y40  F9000
G0 X-135 Y100 F9000
G0 X-90  Y80  F600
G0 X-110 Y40  F9000
G0 X-135 Y40  F9000
G0 X-135 Y100 F9000 E5
G0 X-123 Y100 F9000 E-0.2
G0 X-123 Y70  F9000 E-0.2
G0 X-123 Y100 F9000 E-0.2
G0 X-123 Y70  F9000 E-0.2
G0 X-123 Y100 F9000 E-0.2
G0 X-123 Y70  F9000 E-0.2
G0 X-123 Y100 F9000 E-0.2
G0 X-123 Y70  F9000 E-0.2
G0 X-123 Y100 F9000 E-0.2
G0 X-123 Y70  F9000 E-0.2

G0 X-90  Y100 F9000 
G0 X-130 Y100 F9000 E-0.1
G0 X-130 Y70  F9000 E-0.1
G0 X-130 Y100 F9000 E-0.1
G0 X-130 Y70  F9000 E-0.1
G0 X-130 Y100 F9000 E-0.1
G0 X-130 Y70  F9000 E-0.1
G0 X-130 Y100 F9000 E-0.1
G0 X-130 Y70  F9000 E-0.1
G0 X-130 Y100 F9000 E-0.1
G0 X-130 Y70  F9000 E-0.1

G0 X-110 Y40  F9000
G0 X-135 Y40  F9000

; Return all motor currents to 100%
M400
M913 X100 Y100 Z100

https://youtu.be/mOiIhcDv36Q

@deckingman yeah I know about unlisted but on this YT account I just send stuff and leave them there, nothing to hide, but nothing "consistent". But I used imovie for that prev video to join 2 videos

deckingman

@arhi Neat - I really must find time to stat looking at conditional gcode.

Danal

This works reasonably well. Orange silicone strip is aircraft baffling material. Just tried it because I have a ton of it. It is stiff enough that when dropped into a three sided slot, it wipes plenty well. Tool mounting always makes three passes over this; no intelligence, just does it every time.

0:/sys/tpost0.g
; Runs after firmware thinks Tool0 is selected
; Note: tool offsets are applied at this point!
; Note that commands prefixed with G53 will NOT apply the tool offset.

G53 G0 X1        F5000				; Square move to avoid diagonals. 
G53 G0      Y350 F5000  ; Rapid to the approach position without any current tool.  This lets the human know the next command is waiting on this new tool. 
M116 H1                 ; Wait for set temperatures to be reached

M302 P0                  ; Prevent Cold Extrudes, just in case temp setpoints are at 0


G53 G1 Y373 F2500        ; Move to the pickup position with tool0.
M98 P"/macros/tool_lock.g" ; Lock the tool
G53 G1 Y355 F2500        ; Retract the entire tool and wipe Backwards.
G53 G1 Y370 F5000        ; Wipe Forwards.
G53 G1 Y355 F5000        ; Wipe Backwards.
G53 G1 Y370 F5000        ; Wipe Forwards.
G53 G1 Y275 F5000       ; Wipe Backwards and get clear of tool row, in case next move is large X move. 

G1 R2 Z0        ; Restore prior position now accounting for new tool offset

Sample resulting print, no cleanup at all, straight off the bed. NOT perfect (for one thing it needs more shells on the 'top' curved areas), but pretty good in terms of clean transitions. With a little bit of post process, it became really nice.

IMG_0421 (1).jpeg