I just ordered one also. Looks like a good product.
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Haven’t tried the Bambu PA-CF, but the eSUN PA-CF works great. This was printed using the 0.4mm nozzle using the Bambu PA-CF preset with adjustments to nozzle (260C) and bed temp (60C) on the engineering plate and liquid Bambu glue. The brim lifts slightly at the end. For what it’s worth, the spool was in a dryer for this print. I have used this spool in the AMS as well.
Swim_Missile, schmitzna makes a good point about printing in a dryer when printing PA for 12+ hours. Nylon (or PA filament) sucks up moisture so fast its crazy. I saw a TDS that said some PA CF versions soaks up 50% of their maximum moisture level in the first 24 hours out of the bag at 55% relative humidity (pretty normal level, not very humid).
Since you are going for 12 hours and experiencing clogging issue deep in to the print, it makes sense to suspect the filament is just getting saturated and the print quality degrades enough to clog. The AMS is pretty good about moisture, but if there is a 40-45 % relative humidity level in it after swapping filaments, that could make a big enough difference. So at a minimum, double check your AMS desiccant is good, but consider printing from a dryer.
Like others have said, a larger nozzle will help as Bambu suggest 0.6 as the best to manage clogging and quality, but the 0.8 could help further with clogging (my guess, never tried a nozzle that big). Bambu’s 0.4 nozzle profiles are very good, but there is a distinct lack of 0.6 nozzle profiles, so you’ll need to experiment.
Schmitzna, I’m curious… have you tried using Bambu’s PAHT CF bed temps? Bambu’s filament is suggesting 80-100C, and that would help with the warping you’re finding. If you can keep the chamber temps at the Glass Transition Temp of 70C, the warping should disappear. Unfortunately, the X1 can’t do chamber temps that high, but the higher you can keep it, the better the warp mitigation will be.
Are you actually using the AMS to feed the PA-CF? I was under the impression that Bambu didn’t recommend using the AMS for abrasive materials like CF and GF?
That being said I’ve had great success using Polymaker’s PA-CF. I’ve not printed anything over 12 hours with it, but I might be able to set something up this weekend.
Bambu now state’s PAHT CF is now compatible. But that isn’t for all CFs. For example the PET CF is not compatible, but PETG and PLA CF are.
I have printed a few different brands of PA-CF on the X1 with a 0.4 nozzle without clog issues. But the AMS will not work for long prints in my experience due to moisture absorption. Some of the PA materials I’ve printed become unprintable in less than 2 hours in the AMS in my environment. PA absorbs moisture so fast it’s crazy. I’ve never seen clogging issues but lots of other issues come up and prints will fail constantly if the PA is not well dried and printed from a dry box with good desiccant and a good amount of it. The desiccant pouches in the AMS are not good enough in my experience. I really like PA12 because it absorbs much less moisture and is easier to keep dry. All the PA I print is dried before using (even fresh out of the vac pack) and then stored in a vacuum chamber.
I’ve seen a few videos on YouTube where people came to the conclusion that the AMS even with aftermarket desiccant packs is not capable of keeping filament dry. I think CNC Kitchen has it right printing directly from his food dehydrator.
Actually that gives me an interesting idea. What about making something that would fit under the AMS to hold a small heater and a fan to circulate air through the AMS. Probably would require modifications to the AMS though. But I’m thinking a reptile heating pad with a heat sink on top and low-power fan to blow cool air across the heat sink… hmmm…
Back on topic, I’ve had pretty good success with Polymaker’s PA612-CF. As you probably could already tell from the name it’s a PA6/PA12 hybrid. I have some of their PA6 and PA12, but I’ve not gotten around to trying it out yet.
I will try that next time. The eSUN TDS recommended 45-60C bed temp for their PA-CF so that is why I used 60C.
No prblem, I just saw it as something to know, not that you are doing anything wrong. Actually, quite the contrary, eSun advertises it as being warp free, which means to me they could have a special blend of polymers that changes the normal Nylon/PA behaviors. So, I would work up to the higher temps and see if they create any odd reactions, but I’m assuming they are claiming low warpage because of the CF mixed in. However, I’m pretty sure 80C would be ok and don’t think it will be an issue up to the 100C. The eSun TDS specs look very similar to normal PA6 CFs.
Do you also have problems with dimensional stability with PA-CF from Bambu Lab? We can’t get a grip on the dimensional stability. The test cube is 30x30x30mm.
Measurement result:
X 30.05mm
Y 30.13mm
Z 29,67mm
Am quite annoyed.
Filament has been dried at 80°C for 12 hours.
a.lange, I guess its relative. I don’t expect ANY of my prints to get much better than you’ve got there. Being .05mm, .13mm and .33mm is about as close as I would expect. Sure, the Z dimension could be 50% better IMO, but in all honesty, expecting a molten strand of plastic to match an good CNC’ed part’s repeatability might be too much.
As far as option to help you get closer to what you want, first, I’d say don’t go crazy to hit the number any closer than .10mm. You can do better than that, but I would waste that much time and filament to get there. To get the Z compensated, I haven’t found a compensation factor for that, but you can tune the extrusion of it to improve the dimensions. Because the Z dimension is basically all to do with the how accurate the extrusion is, you want to make sure the K factor, flow ratio, and pressure advance is perfect.
I have completed two 8.5 hour prints and then on the third it printed great until maybe 5 or 6 layers from the top then it clogged. hardened extruder, hardened nozzle, textured bed plate - stock settings for PLA-CF - was nearly 1 full roll to print 3 of the pieces. I really hope I do not have to replace the nozzle after every two of these pieces, I have 17 more them to print… Attached image is of the 3rd piece - it really is only the top few layers as in looking at side profile it is fine right up to the top.
How about putting the entire AMS inside a drybox that’s large enough to hold it? Hey presto you cut off any new moisture from entering the AMS. Admittedly a kludge, but at least it would be fairly easy to put together.