I print from 3KG rools of PA612 and PLA and I am getting overwhelmed by the error telling me the filament is tangled or something. The spool spins freely. Is there a way to turn down the sensitivity of this?
The high inertia caused by the weight is triggering this message.
The extruder motor is servo based and measures constant torque. It is therefore quite sensitive when it pulls and feels the sudden drag.
If you have a TPU feeder at hand, you might try that. It basically shifts the peak to the TPU feeder so the extruder is not triggered anymore.
No guarantees though.
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Well for a 2K dollar machine I am not impressed. Bambu need to address this ASAP
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They did. That error is a protection. The mechanism probably isn’t designed to handle such heavy pulls and there is also the opposite problem with tape holding filament to the spools or other ways filament can hang up through over/under tangles or slipping down the sides of the spools. You want the feed mechanism to cry uncle instead of self-destructing.
You could respool the big spools onto standard size spools and eliminate the problem.
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I wasn’t designed for 3kg spools by default. Like Gerrit said, the added weight is trigging a safety to prevent overloading the extruder motor. Outside of the TPU assist motor, only thing I can think of would be to try and print a 3kg spool holder that is on bearings, this should reduce the friction more than a traditional external spool holder. Or try direct feeding from above without the glass top, bypass the buffer and go straight PTFE to extruder. If your running 3kg rolls, you likely arent doing anything multicolor and aren’t using an ams.
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Reduce drag as much as possible, get bearings on whatever is rolling the spool. Analyze your PTFE route and make sure it isn’t silly
So does it say that in writing anywhere that is can’t print 3K spools? And If that is the case in my opinion that is very sorry to have a 2K dollar machine that is suppose to be a work horse and a production printer for print farms that does not have an extruder that can pull a spool that has no drag on it from directly underneath it. I have a crappy FlashForge that fed this stuff like it was water. I have heard nothing but good things about Bambu now I am wondering if I should have bought this printer at all.
Feed mechanism destroying itself. Guess what I expected is the brand Bambu (supposed to be the BEST) not engineering an extruder that can pull from a 3K spool in the Left nozzle is sad. Guess I am stuck with the problem and as far aa respooling it…. AHHHHH No not gonna happen. That is why I buy the 3k spools prince and conveinece.
Feed/jam issues are real and that safety cutout is to protect hardware. They could certainly do something like weigh each spool and decide to increase the allowable stall power but then it’s extra cost and features few would use.
If you have ever seen the 4-into-1 adapter to combine multiple AMS units, that’s easily something you could build yourself (that is just one to one) with a pinch roller mechanism so that whenever the slack to the printer is running low, contacts close and a motor runs for a moment, and the pinch roller pulls more off the 3kg spool and restores the slack.
That way the feed mechanism never has to pull from a 3 kg spool and you can use 3 kg spools.
If 3kg spools are that important to you, you could be in 3 kg nirvana much quicker with some time spent making that real. Doubtful Bambu is going to change things up for you unless a bunch of others out there want it too, but then you’ll be waiting. This is the first mention I’ve seen here of 3 kg spools. Maybe I missed it but 1 kg is much more common and is what is supported.
The resistance it’s feeling when it tries to unwind a 3kg spool is the exact same resistance it feels when a regular spool of filament begins to develop a tangle or other feed issue. There’s no practical way to “sometimes” detect it’s having to work harder than normal to feed filament.
What you CAN do is look into the TPU assist module, it functions as a “middle man” to help pull filament along and help the main extruder gear have an easier time. Some users have tried it with PPA-CF, a notoriously fickle filament to feed, and have had good results, so I don’t see why it couldn’t help you with your issue.
Well I am extremely disappointed that this machine is not the end all I was told. I have farted with FF machines for over a year working on them more than I print it seems. I don’t expect no issues but I just had to disassemble the extruder due to ABS stuck in the extruder gears. It’s a true pain in ■■■to get in there and do this. Next time, won’t be as bad but it seemd to me they could have made it simpler, maybe not. I just was told from many folks Bambu printers just work. I have printed to my FF machines with 3KG rolls. Do you guys not want to save money? Buying 1KG rolls gets expensive, especially when buying the PA612 nylon. I have to print the firearms I build and sell, I am a 07 FFL so legal for me to do this. I still like the printer. The TPU assist one is 60 bucks and 1 is 137, what is the difference?
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I have been printing from 3kg spools day in and out with the X1C directly into the extruder. Besides a low friction spool roller, the key is having a long enough bowden tube going to the spool. That acts very similar to a buffer: When the extruder pulls filament in, the bowden just pulls closer to the spool. the spool then starts rotating so that the bowden slowly relaxes again.
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Bambu’s entire current company revolves around the AMS.
You’ll note that those only support 1kg spools, and only a subset of 1kg spool shapes, and they do not sell non-1kg spools. I think the company makes it pretty apparent you’re on your own if you wanna bring big spools. Try adding some bearings to the roller, it really makes a difference. Alex also makes a good point and that if you add an extra meter of PTFE in the line, you give it a very easy start to the motion, and you may even need to do something like reduce your retraction speeds so it has more time to accomodate
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I have yet to run into a real discount on 3kg rolls compared to 1kg. I get my petg for around $12 a roll, 3kg seems to run around $35, ABS I buy at 13.99 per, haven’t looked into 3kg prices.
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You are printing guns and the price difference between 1kg and 3kg plastic spools is what makes a noticeable difference in your manufacturing? Could you please shed some light on this? Guns aren’t known to be cheap products.
To me it sounds like SpaceX complaining that raw sheet metal steel is too expensive and a major setback all while generic farmers use it in similar quatities for granaries… Please don’t take it as offence, I am genuinely curious and not sarcastic, I just try to better understand what am I missing in this context.
Have you ever killed someone, cut them up and put them in a sack?
If you have, you know how hard it is to drag that sack along the floor as there is resistance.
Now, imagine you killed an entire family or a very large person.
That becomes a bigger problem and you may need two or more people to pull the sack.
That is your problem.
Printer that are designed to use much larger spools usually employ a push and pull method, essentially, more than one motor and often a motorised spool holder. Either that or the motor in the print head has to be far stronger, thus means bigger, which increases weight, which means slower and less accurate quality surfaces.
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In most cases they do just work. I’m going to guess you have tried it with 1kg spools and that was fine? If so, your printer works too. My car just works but I don’t expect it to be amphibious. It was sold as a car and I bought it as a car. Should I be upset I can’t cross a lake with it?
Your use case is different. I don’t have the space to store all the colors I have if they were 3kg spools vs 1kg. I’d bet many here are in the same boat. Price isn’t the issue for me or probably many others.
The bowden tube solution sounds good but even if it works for you, it’s still going to be extra strain on the extruder feed mechanism and you may need to replace parts sooner. That isn’t a problem with the printer if it happens. It’s using the printer outside of recommended operation.
People are trying to help you. You’re going to need to put some effort in if you are going to insist on using 3kg spools.
Um, interesting analogy, Malc. 
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Bambu would say they addressed it by making the AMS.
Load 3* 1kg and trust it to reload.
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???
(This is a joke. I understand that he means farmed. However M and T are very far apart on the keyboard.)