I’ve been printing items without issue since I switched to the 3D module a couple of weeks ago. My latest print started off fine, just like the others. When I went to go check on it a little while later, I found that the magnetic print mat had been pushed off alignment and the head was completely covered in filament.
What would cause something like this? Is it recoverable? I got off what I could, but the rest is pretty hard stuck on there. I just purchased this thing and put it together on September 29th. Is this covered under warranty?
Was able to get most of it out, but there is still filament down deep in it. I might have to take the whole thing apart to be able to get to it. It also appears that some of the wire covering at the bottom might have been ripped off. Are there any instructions for taking this apart?
Unfortunately, this is not an uncommon issue. What probably happened is the print head collided with the print and dislodged it, causing the print to get stuck to the head. This can cause a pocket to form that the nozzle just keeps pumping filament into, forcing the hot plastic into and around the head.
This is one of the less severe cases I’ve seen on the forums, and as long as the circuitry inside the printhead didn’t get damaged, you can just swap in the spare hotend that came with your machine and use that as you try to recover the one that got covered.
Unfortunately, this isn’t covered by the warranty as it can technically be considered “user error” but from what you’ve shown, it looks like you should be alright. The fan shroud looks intact, as does the silicone sock on the affected hotend. I would recommend looking inside the printhead with the hotend removed to try to see if the plastic got further inside it than what is shown here and if you do use this head again, to watch it for a while to make sure it doesn’t have any weird or dangerous behavior.
Thanks for the reply @bobby4718. After I removed the hot end, it looked fairly clean inside the module. I recently moved, so couldn’t find my heat gun, so I just went ahead and installed my spare hot end. I looked up the prices and they are relatively cheap, so I went to order a couple more. The shipping cost, made me go look on Amazon, and sure enough, they had them there for free shipping, so go some from them.
I loaded the filament, ran a bed calibration, and am currently running a print test job. So far so good. Will know for sure in another seven hours…
The solid blob coming out of the back of the heater block (and not the filament tangle) is the result of a manufacturing defect in the hot end. In order to avoid getting blobs, the heat break and nozzle need to be torqued adequately. If not, they don’t mate correctly. The result is a leak through the would-be mating surfaces and then a spiral leak up the threads.
Demand a replacement for the hot end at minimum. If there’s permanent damage to the head as a whole, that by rights should also be covered.
@eh9 how can you tell that it’s from a loose heat break/nozzle rather than from filament backing up from the blocked nozzle? (I want to make sure I don’t give incorrect info in the future)
For reference here is a classic example of leakage from improper assembly at the factory:
That happens when the nozzle is torqued against the heat block instead of against the heat break. The nozzle needs to face seal against the heat break. Failing to do so leaves spiral leakage paths out both the top and bottom threads of the heat block.
There are some similarities in what happened here.
Thanks, @eh9! I’ve only been using it for 2 weeks, is this something that doesn’t show up until after some use? The first several items that I printed were fine and only started to run into issues when I tried printing larger items. Before this happened, I started to get some print failures and the problem seemed to be getting worse. It started when I tried to print this Cthulhu dice tower:
It failed while trying to bridge that gap. I canceled it and started on a different dice tower that would print without needing supports. That’s the one that turned into the mess I started this thread with.
It varies. Spiral leaks are generally high-friction, but with enough time*pressure, they’ll leak. If you catch them soon enough, they might not get very bad. It should be standard procedure to inspect a newly-installed hot end after some use to make sure it doesn’t have problems.
And don’t think that once good, it’s good forever. The hot end has three materials: stainless steel, aluminum, and brass. All three have somewhat different coefficients of thermal expansion. Given enough thermal cycling (expansions and contractions), all the movement can cause threads to loosen. Sometimes. You might get lucky, but you inspect because you might be unlucky.
They’re not exclusive. If there’s a defect in the heat break/nozzle mating, all it takes is enough pressure to overcome the resistance of the leak. That can happen in ordinary use, with the ordinary pressure to push molten plastic out the nozzle. It might also be that, sometimes, it takes the higher pressure from a back up in filament feed that generates higher pressure. Or it can happen in both cases but happens significantly faster at higher pressure.
This was the hot end that came with the machine, so I didn’t install it. By inspecting, do you mean that I have to physically remove it from the module to examine it, or just a visual look at it in the module?
This is the test print with the new hot end. Is this typical of these machines, or can it be better?
Notice how it starts to look jacked on the overhangs? I think I did this on the Luban Fast print settings. Although, I did reduce the speed at the machine to 80% before starting the job.
By inspecting, I mean to look at both places on the heater block where a spiral leak could come out. One’s at the top of the block and one’s at the bottom. The one at the bottom is easy to see; just look at the nozzle and make sure there’s no plastic seeping out from the threads. The one at the top is obscured; you’ll have to drop the hot end out to get a look at the top. That need not require unplugging it, although it might be easier to do so.
The point of the print tests like that is not to achieve perfection but to push the machine past it’s capabilities so that you know where that limit is. Part of it is supposed to fail.
I think your’s looks pretty good, but I’m not that much of a 3d perfectionist. Someone else will have to point out some particulars you might want to try.
