If I printed a PLA model with both nozzles then I want to print an AMS model next only using the right nozzle how can i remove the remaining PLA in the left nozzle so it doesn’t soften and clog the nozzle during the AMS print because of the chamber temperature? This just happened to me and had to disassemble the extruder because a piece of filament broke off in there trying to push through a clogged hot end. Thanks in advance.
Just Remove the left nozzle
This seems like the best option. I guess i could also just load some ABS into the unused nozzle as well. This seems like something Bambu Studio should warn users about before printing an ABS print. I don’t see how the nozzle wouldn’t clog if you printed with PLA before ABS. I think this is the second ABS print i did with the H2D but the only other time was my very first print so there wouldn’t have been anything in the nozzles. So the very first time i printed a single nozzle ABS model after a dual color PLA model the nozzle clogged. On top of that not only did I have a clogged nozzle, which is an easy fix, but I also had broken filament all jammed up in the extruder. But thanks to good documentation from Bambu I was able to take apart the quick change tool interface and remove the problem in around 20 minutes. Just seems like something that was overlooked and will cause many people problems over time.
I’ve printed plenty of ABS in the P1S before, after PLA prints and can’t recall ever having a clog. If your ABS or PLA are breaking easily you would probably benefit from drying it a bit more.
I have nearly 1000 hours on one P1S and have had 3 clogs, all my fault, all with PLA and heat creep.
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I have over 2500 hours on my X1C and it never happened either, but just like the P1S it doesn’t have 2 hot ends or a heated chamber. The problem is if you are printing a single color AMS model after printing a dual color PLA model there is PLA still remaining in the one nozzle. So when the chamber heats to 65c the PLA in the unused heatbreak starts to melt causing the clog. This is something that will only be a problem with dual or more hotends.
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I was worried about that a week ago, when I was printing ABS (chamber at 65C) while the other nozzle still had PLA loaded from the external spool.
However, after printing (and cooling) the PLA nozzle wasn’t clogged.
Imho the clogging is happening when you are trying to feed with those high chamber temperatures.
Still not a 100% guarantee, it won’t clog,
In my case it was Bambu Basic PLA.
If you are worried, load and unload the inactive nozzle and you will have whatever filament you are using in the right also on the left. Problem solved,
I understand now. I wasn’t thinking about the heat break.
That is a solution but imagine having the Vortek system… So you will need to load 6 nozzles with the abs before printing. Im thinking pulling the nozzles would be a better option.
In that case, removing them from the chamber is certainly easier, faster, and more cost-effective.
I swap from PLA to PETG to ABS/ASA and then PC all the time and I never considered what was in a nozzle I wasn’t using. Maybe I’ve been lucky.
On the H2C with the induction nozzles - it’s cut and pushed back in so far that I don’t think you’d have an issue. But on the non-induction nozzles the filament is sticking out of the top after it’s cut…
That said pulling the induction nozzles out of the H2C is really really easy to do.
I’ll just have to keep this in mind when I swap to something like PC from PLA…
I’ve never had a problem like this from switching between PLA/PETG/ABS/ASA on my H2D. The only material I’ve ever been concerned about is TPU, but I use a dedicated nozzle for TPU to keep issues to a minimum. Maybe investing in dedicated nozzles if you see problems or have a concern. ~2300 hours on my H2D
Ya I’m not sure if I was just unlucky but it just kinda makes sense because when I pulled the PLA nozzle it was all melted in the heat break. Had to use the Allen key method to unclog it. I mean a 65c chamber is going to melt the PLA on a longer ABS print.
The Glass Transition Temperature is below 60C for PLA. But the melting temperature is starting around 150C.
Surely PLA gets soft in a 65C environment, but if the weight of 20mm of filament is enough to clog the nozzle might be disputed.
Surely if you try to purge a PLA filled nozzle when the heartbreak is 50C+ can cause a clog though.
But as I mentioned earlier, I had a PLA filled nozzle dormant for 2+ hours in a 65C chamber during an ASA print job, and after cooling the nozzle just functioned fine.
The H2D doesn’t allow you to start a print job with PLA until the chamber temp is <=40C.