Core One+ nozzle clogging after 10 days – defect or normal?
Hello,
I purchased a Core One+ about 10 days ago. I’ve been printing intensively every day using PLA, as well as two prints in PETG. Everything was perfect.
However, for the past two days, the nozzle has been clogging during a PLA print. I tried cold pulls and inserting a needle, but nothing worked. The nozzle extrudes for about 2 minutes and then clogs again. The only solution was to replace it with a standard flow E3D nozzle.
I find this disappointing for a printer that is supposed to be durable. I’ve had an MK3S for 7 years and never had to change the nozzle even once!
Is the nozzle covered under warranty? If it needs to be replaced every 10 days, it’s going to get expensive. There also seem to be quite a few reports of clogged nozzles on the Core One. Could this be a defect?
I would like to point out that I have only used brand-new PLA and PETG from Prusa, and the ambient temperature does not exceed 35°C.
Aside from this issue, when it prints, it is absolutely exceptional!
RE: Core One+ nozzle clogging after 10 days – defect or normal?
"and the ambient temperature does not exceed 35°C."
-> The HeatBreak does not exceed 35°C and chamber temp does not exceed 28°
RE:
Nozzles don't wear out in 10 days. [Edit: someone's going to say "unless you run lots of abrasive filament through it. That doesn't apply here as you're printing PLA.]
The problem with high-flow nozzles is that they're internally more complex (multiple channels through the nozzle, making them somewhat more prone to clogging and much more difficult to clear if the do get clogged.
I'd recommend using some cleaning filament with the HF nozzle to see if that helps the nozzle come back to life.
RE: Core One+ nozzle clogging after 10 days – defect or normal?
Thermal grease on the cold end of the nozzle (or everywhere) might help, it's just messy.
For problematic filament you could consider reducing retract distance and speed (say, cut both in half).
Oiling filament is controversial but might fix it.
I use all the above.
RE: Core One+ nozzle clogging after 10 days – defect or normal?
IMO, unless you can test and show it's accomplishing something, you might not need retraction at all. I'd try setting it to zero or unchecked.
You should get 6 - 9 months use from a brass nozzle with plain PETG/PLA although white filaments and fillers will reduce this.
Open the nextruder, take a metre or of scrap PLA, heat the nozzle to 5°C above the working temperature of your hottest printing filament. Bypass the gears and feed the PLA into the top of the nozzle tube...
Now push the PLA through the nozzle manually, slowly at first and then as fast as it will go; finish by pulling the last of the filament out as fast as you can.
This should shift any PETG remaining in the nozzle and leave it clear.
I've never seen the point of HF nozzles, they only print faster in ideal cases and cause far too much trouble.
Cheerio,
RE: Core One+ nozzle clogging after 10 days – defect or normal?
Hi, here’s another update based on my experience. I had another nozzle clog while printing with Prusament Galaxy Black PLA, just like the first time. The heat break temperature was fluctuating between 38 and 40°C. This time, I was able to unclog my normal flow nozzle quite easily. Since then, I’ve printed large parts with the same filament with the door open and haven’t had any issues. I think the heat break cooling is a bit insufficient with certain filaments like Galaxy Black if you want to print reliably with the door closed.
RE:
Hi, here’s another update based on my experience. I had another nozzle clog while printing with Prusament Galaxy Black PLA, just like the first time. The heat break temperature was fluctuating between 38 and 40°C. This time, I was able to unclog my normal flow nozzle quite easily. Since then, I’ve printed large parts with the same filament with the door open and haven’t had any issues. I think the heat break cooling is a bit insufficient with certain filaments like Galaxy Black if you want to print reliably with the door closed.
In this case, it matters how old the filament is and whether it's dry. Galaxy black is mixed with carbon black and mica glitter, whereas white is titanium dioxide (usually), so there can be thermal differences due to the chemical differences of these additives, but not enough to suggest that black creeps more than white. I'd start by drying the filament, checking the retraction distance, heatsink fan and maybe lower the nozzle temperature by 5–10°C
RE: Core One+ nozzle clogging after 10 days – defect or normal?
In my opnion, heat creep issues with PLA are strongly related to the design of many current hotends where the nozzle and heatbreak are a single part. This is very convenient for nozzle changes and avoids possible filament leaks when the nozzle is not tight against the heatbreak, as in the V6 system but there’s always a catch. The fact that nozzle and heatbreak are integrated means that the ”neck” of the heatbreak can’t have very thin walls or else it could be damaged (broken/bent ) when we handle it to install or remove a nozzle. The thicker that neck is, the less efficient it becomes insulating heat from the hotblock and if the temperature inside the heatbreak raises too much -> filament jam.
No way to change that with the Nextruder or other designs where nozzle-heatbreak are a single part. Period.
The only approach (that I know of ) really fixing PLA heat creep is the Mosquito design, original or Chinese clones. Here the neck of the heatbreak is an extremely thin steel tube, because all the mechanical stress is taken by 4 tiny binding posts joining the corners of the heater block and the bottom of the heat sink. I had often heat creep problems in summer with my MK3S+. Since I replaced the stock hotend with a Mosquito five years ago I’ve had zero issues, no matter if room temperature was 30C or above.
RE: Core One+ nozzle clogging after 10 days – defect or normal?
I concur, and this, along with a mix of wet filaments, is often a primary cause of clogs.
Hi, here’s another update based on my experience. I had another nozzle clog while printing with Prusament Galaxy Black PLA, just like the first time. The heat break temperature was fluctuating between 38 and 40°C. This time, I was able to unclog my normal flow nozzle quite easily. Since then, I’ve printed large parts with the same filament with the door open and haven’t had any issues. I think the heat break cooling is a bit insufficient with certain filaments like Galaxy Black if you want to print reliably with the door closed.
In this case, it matters how old the filament is and whether it's dry. Galaxy black is mixed with carbon black and mica glitter, whereas white is titanium dioxide (usually), so there can be thermal differences due to the chemical differences of these additives, but not enough to suggest that black creeps more than white. I'd start by drying the filament, checking the retraction distance, heatsink fan and maybe lower the nozzle temperature by 5–10°C
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Chuck H
3D Printer Review Blog