So because I am new here I wanted to know if there is a procedure for clearing clogged nozzles. I went and researched it an to no avail they all failed. With the FF it’s simple cut the filament, heat the nozzle, use the tool provided to clear nozzle. The hotend satys in the printer and you loosen the extruder gears to allow the tool to be pushed into the hotend. You can get some leverage and usually get the clog out.
These hotends won’t work that way, I finally had to just cut the filament and remove the hotend so there is a piece maybe 1/8” sticking out the topod the hotend. My only other way I can come up with to fix is putt hot end into vice and heating the hotend with a MAP torch and push in a tool to force the filiment out.
Do yo guys have any suggestions?
I’ve never had to do any of that. I just heat soak the nozzle with way more temp than needed. Wait for a minute and manually extrude (with the printer controls) more filament. Any clog is no longer a clog when the filament is turned to soup. Been my experience anyways. But I’ve only had one clog in about 4 months and that was do to a storm lol.
yea tied that , I am printing with PA612 which is harder to deal with. Thanks
@truckeic ok, first off, be careful with that MAP gas.
MAP temps run up to 3,730°F (2,054°C).
Max temp on a hardened nozzle before it looses structural integrity is going to be 842°F to 932°F (450°C to 500°C).
PA612 will burn to carbon at 350°C to 475°C. not a lot of wiggle room there.
I was going to suggest using PC (Polycarbonate) for it’s higher glass temp, but then I remember PA612 and PC don’t like each other like that.
Ok, this is the only other thing I can think of.
Take a section of SWG 16g copper wire and scuff about two inches from the lead with a bit of 80 grit. this will give it some tiny burs and grovels. Leading into the channel the burs will get pushed back towards your hand. The copper is soft enough that it’s not going to scar the inside of the nozzle, and the SWG 16g is about 1.63 mm (AWG 16g is about 1.29 mm). Small enough to get into the main channel but to big to prevent it from getting into the 0.4 mm channel (if you have something stuck in there, uses the acupuncture need provided with the printer). Give the copper wire a very quick warm up, then send it down the channel while warming up the nozzle/hotend, Then allow to cool below the PA hard point. The PA will flow into the tiny groves made by the 80 grit while it’s hot. Once cooled, you should be able to pull the whole mass out as one. It might take a few shots to get everything.
If it doesn’t, work… well, most nozzles are fairly cheep.
Oh and use a cigarette light. Much safer.
Edit: Grammar and Spelling
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@truckeic sorry had to make a few changes there.
1.5mm allen wrench, heat up with a torch and push into the inlet end of the nozzle, allow it to melt as it encounters filament, let it cool, then pull it out. It’ll take a plug of filament with it.
Clean off the tool and repeat until you’ve cleared the whole thing - you may actually push the last bit out of the nozzle, if not, load in some small bits of soft filament (preferably something that sticks to nylon), repeat the hot allen key trick and keep pulling after it cools, sooner or later you’ll get whatever was in there.
@CarbonForge So, just curious, aren’t your concerned about abrading the inlet walls consider both the 1.5 mm Allen Key and nozzle are similar hardness?
Stainless Nozzle: 20-30 HRC
Hardened Nozzle: 50-65 HRC
Allen Key (Tool Steel): ~52 HRC
SWG 16g Copper Wire: 10 HWB/ less than 0 HWC
Interesting question, had to think about it for a second, but I’m confident the answer is not even remotely.
First, actual potential for abrasion is minimal - molten filament adds some lubricity, and the actual amount of contact just isn’t sufficient to result in any real wear.
Second, the heatbreak section of the nozzle isn’t especially dimensionally intolerant; a few hundredths of a mm won’t matter. That area just acts as a “buffer” for filament prior to being extruded, it’s truly the tip of the nozzle that only matters.
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unless it’s completely clogged, you can always just cold pull. even if it’s completely clogged, you can still start with the unclogging needle/pin poke:
poking can often make it at least partially flowing, then you can continue to do a cold pull:
repeat the cycles of 320c, 290c and 250c, until it’s completely clear. might take a couple cycles.
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So, I’ve heated up my hotend, with a torch, in the past to remove pps-cf and pc-cf clogs. What happens when I cook/burn those out? Wil this ruin the walls on the inside of my nozzle? Seems like I am getting more clogs than necessary - Perhaps I have my flow set too high ~ 15mm3/s on a .8mm nozzle? You’d think with a .8mm nozzle the risk of clogging would be very minimal. I’ve also heated up my nozzle so I could slide the whole hotend melt sleeve up closer to the cooling flanges.
edit: I will say the reason for my using the torch is that 350c did not seem to cook out the filaments, but perhaps I simply didn’t wait long enough
Cheers
Don’t use map gas and learn from my mistake. I tried it and the nozzle popped off and fired across my garage LOL.
PPS and PPA are tricky - the reason they give that lovely “ring” sound when tapped is due to how they cure after printing. They form a sort of crystalline solid and interlink (including between layers to some extent) - and that process is definitely happening inside nozzles with any filament that sits in the melt zone.
The first step is prevention - definitely unload that filament immediately after use, and purge the nozzle with something else high temp but not fiber filled until it’s very clearly running clean.
But when clogs happen anyhow? The way I see it, if you can’t clear it with cold pulls, heating it externally is the only option. I like clearing as much of the nozzle as possible using a 1.5mm allen key to do cold pulls, then insert a slug of white/clear PC filament in the back, heat the tip up with a torch, and push it through, hopefully taking any other junk with it.
Will it damage anything? If the alternative is a useless nozzle, what do you have to lose? The biggest issue when heating far above the usual 300/350 max for these nozzles is 1) losing it’s heat treatment 2) softening the crimp and the nozzle popping out and 3) filament residue decomposing and leaving gunk/tar materials in the nozzle. Best practices are to limit the heating as much as possible, so a less intense torch, propane rather than MAPP, tuned to a lower temp flame, and limit heat as much as possible.
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Cleaning out the nozzle between prints… Prevention - that is something I haven’t tried yet.
Maybe that would get rid of some leftover residual fibers, that could potentially create clogs later.