nozzle wipe

zapta

@CaLviNx said in nozzle wipe:

I print almost exclusively with petg (das-filament) and after I carry out the initial wipe I don't suffer from build up on the nozzle at all,

Any suggestion what kind of settings to loo for to avoid buildup? I am using 2mm retraction, 0.95 flow, and 245C. BMG direct extruder + E3D hotend with 0.4mm brass nozzle.

A Former User

@zapta

First thing is "squish" petg doesn't like being squished into the bed like PLA does. You could be quite alarmed at how much further away from the bed petg likes to be. On my chiron I run a BMG with an e3d nozzle and the retraction on it is all the way upto 5.60mm retraction speed of 40.0mm/s.

I also force retraction between layers (in simplify3d)

deckingman

@arhi said in nozzle wipe:

It looks exactly the same ................

....................I always say assumption is mother of all fsckups and when I do assume I'm sure to be clear that I don't "know" but just assume (actually maybe assume is wrong term here, "suspect" or "almost believe to be" might be more correct)

Sure it might look the same but that's hardly a basis for assuming, "suspecting", or "almost believing" that it is the same. Taking a quick gander at the relative specs, E3D claim a hardness of 60 HRC for their X nozzles while Slice Engineering claim 65 HRC. Given that the Rockwell scale is logarithmic, that's a big difference in hardness even though they "look the same".

One of my neighbours has a cat. It has 4 legs and a tail. My other neighbour also has a pet which has 4 legs and a tail. At night and from a distance they look the same. Do you therefore assume, suspect or almost believe that the other pet must also be a cat? (Hint - one mews the other barks).

Not sure how we ended up here but we've gone way off topic. Nice little chat though......

jens55

@deckingman said in nozzle wipe:

One of my neighbours has a cat. It has 4 legs and a tail. My other neighbour also has a pet which has 4 legs and a tail. At night and from a distance they look the same. Do you therefore assume, suspect or almost believe that the other pet must also be a cat? (Hint - one mews the other barks).

It's a cat speaking a foreign language ....

Phaedrux

@arhi I've been using the same hardened steel nozzle heavily for about 2 years now and I've never managed to get it that messy. The little bit that does manage to cake on comes off easy when heated to 80-90c with a pair of pliers. I use a brass brush too. No coating to worry about. In fact, if anything the steel has been seasoned from use with it's own non-stick coating.

arhi

@deckingman that is a huge difference in hardness so they def. are not same. Dunno if it has to do with the hardness of the underlying material as e3d nozzles are made from something way softer than vanadium :D. Not sure if the rockwell measuring needle can easily measure just the coating (none of the ones I seen could).

We'll see how the slice one will perform I have one vanadium nozzle (hexagon, their experimental one, was too expensive to produce so they never mass-produced them) and I love it even without any coating so I might be a user soon... also with the clone, while the clone is useless pos that does not work it gave me a good understanding of the size and weight of the mosquito so I'm getting me one as soon as I can.

Back to original discussion, I'm thinking hard about the "design" of the "brush" and I still don't see what would be much better than a simple "plate" to brush over (like what you and @danal are using), anything I came up (stacked arrowheads were kinda max I could throw) can be "simulated" by different path over the simple flat plate so I'll just wait for this to pass and use a flat piece of silicone stripe, till then this sponge will have to do

arhi

@Phaedrux said in nozzle wipe:

@arhi I've been using the same hardened steel nozzle heavily for about 2 years now and I've never managed to get it that messy.

I have bunch of printers with very clean nozzles too, this is the nozzle I used to "break this printer in", to get extrusion, heights, sensors etc etc dialed in so there was plowing trough overextruded filament more than once When the printer get dialed in usually nozzle and heatblock only slowly turn black from collecting that abs oil that condenses from abs fumes, or in case of pla/petg they stay super clean

Danal

Fairly heavily used nozzle, wiped over the strip thingie above for all its life.

Danal

Much, MUCH older, same wipe for life, this one really needs to be replaced (it was, a few min later) because of the scratching on the "ironing surface" around the actual hole.

arhi

@Danal after few kg of ABS no matter how I wipe them they never look like that, they exposed parts are all "black" from the ABS oil/vapors

mwolter

Here's a conditional gcode nozzle wipe script using a straight piece of silicone mounted on the back left corner of the frame (no Z coordinate). There might be a cleaner way but couldn't think of one without a modulus or "is even" operator.

G1 X-12 Y332 F24000 ; rapid to inital point outside the wipe strip
while true
	if iterations = 0 || iterations = 2 || iterations = 4 || iterations = 6
		G1 X-4 Y{332 - iterations * 2} F1200
		G400
	else
		G1 X-12 Y{332 - iterations * 2} F1200
		G400
	if iterations = 6
		break

Danal

@arhi said in nozzle wipe:

@Danal after few kg of ABS no matter how I wipe them they never look like that, they exposed parts are all "black" from the ABS oil/vapors

Yeah, those were all PLA, maybe a little PETG now and then. I have literally printed < 1 kilo of ABS in the last five years.

arhi

@Danal I print mostly ABS on most my printers. This nozzle on the image (E3D-X 0.3 ) printed maybe 100g of ABS so that's all PLA and PETG

arhi

conclusion - this silicone sponge, while totally cool for kitchen, disaster here .. total disaster not working at all really ..

I recently removed the blue e3d sock for this black noname sock as this black one is imo better (thicker, harder, stays better on ..) ... and since I'm on white PETG attm it's very visible, I noticed everything is white under, cleaned it manually, wipe, white again ... darn bristles on this sponge are so soft that when nozzle come on to clean the ooze instead of cutting the ooze off it smears the ooze all over the sock and nozzle, again and again and again ... and no matter of swiping head over that sponge helps ... then I tried it manually, to clean nozzle by hand using a sponge and it does not work. Figuring now that's what I was supposed to try before I mounted the sponge but life. If it wasn't for you guys telling me how ugly that nozzle is I might allow this to continue longer

I managed to find original silicone sheet I designed that wiper for. Thin 0.5mm one, I doubled it up and put there. It's nothing special, just works .. I'll upload new script later, tweaking it up, getting inspiration from @mwolter

arhi

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

if state.currentTool < 0
  echo "No tool loaded, aborting the wipe"
  M99

if heat.heaters[tools[state.currentTool].heaters[0]].current < 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 
while true
  ; go around the stripe
  G0 X-110 Y40  F9000
  G0 X-135 Y40  F9000
  G0 X-135 Y{100 - iterations * 3} F9000 
  ; wipe
  G0 X-120 Y{100 - iterations * 5} F6000
  if iterations == 6
    G1 E-3 F3000
  if iterations == 8
    break

; go to park position
G0 X-135 Y40  F9000

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

I need to clean from the same side always cause the silicone is not stiff enough and I didn't want to cut it too close to the petg holder but looks like it works now

arhi

actually turned it around so that the "bend" of the .5mm silicone is what i brush on .. stiff enough so I can go both directions ... this is great

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

if state.currentTool < 0
  echo "No tool loaded, aborting the wipe"
  M99

if heat.heaters[tools[state.currentTool].heaters[0]].current < 200
  echo "Extruder too cold, no point wiping, aborting the wipe"
  M99

; Drop all motor currents down
M400
M913 X30 Y30 Z25

; relative extruder move
M83 

; X-135, Y100 
; X-120, Y60

G0 X-110 Y40  F9000
G0 X-135 Y40  F9000
G0 X-135 Y100 F9000 

while true
  G0 X-135 Y{100 - iterations * 3} F9000 
  G0 X-115 Y{100 - iterations * 5} F6000
  if iterations == 6
    G1 E-3 F3000
  if iterations == 8
    break

; go to park position
G0 X-135 Y40  F9000

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

What I just figured out is that I have this ~1cm of space on the left side of the bed for the whole Y length and that it would be way smarter to use a stiff piece (like @deckingman made taht milled channel) of 1x1cm square "rod" and attach it to front left and back left frame so I have stiff wiper along the whole depth of the printer... need to figure out how to do it, none of my CNC machines have working range of 30cm, maybe do it in 2 passes or just pay someone to do it for me after things go back to normal. Anyhow, this works, yeeey and this new programable g-code is awesome

deckingman

@arhi For info, I'm currently working on a better "bucket". What I mean by that is with a mixing hot end, I sometimes have to purge as well as wipe. That purged plastic has to be collected, otherwise it would end up getting onto the belt that drives the lead screws. My current "bucket" is too shallow and I have to empty it more often than I would like.

timcurtis67

@deckingman said in nozzle wipe:

@arhi For info, I'm currently working on a better "bucket". What I mean by that is with a mixing hot end, I sometimes have to purge as well as wipe. That purged plastic has to be collected, otherwise it would end up getting onto the belt that drives the lead screws. My current "bucket" is too shallow and I have to empty it more often than I would like.

Conditional g code on the horizon.... If bucket.purge == full then empty.

dc42

@mwolter said in nozzle wipe:

There might be a cleaner way but couldn't think of one without a modulus or "is even" operator.

There is a mod(a,b) function but I forgot to document it at https://duet3d.dozuki.com/Wiki/GCode_Meta_Commands#Section_Functions. I'll fix that now.

arhi

@dc42 said in nozzle wipe:

There is a mod(a,b) function but I forgot to document it at https://duet3d.dozuki.com/Wiki/GCode_Meta_Commands#Section_Functions. I'll fix that now.

great

how come you skipped the % operator?