3D printer head got stuck with filament

Snapmaker 2.0
1

Hi,

I have had a bad experience with the Snapmaker. After starting the printing job and returning after a couple of hours the printer was not printing anymore due to filament blocking the printer head. See pictures.

Can anybody explain what happend so that I can avoid this of happening again as I have to buy a new printer head :-(.

Thank you all in advance.

Regards,
Bert

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2

This type of damage is usually due to the print losing adhesion to the bed.

The sequence of events is:

  • The printed part comes free from the bed and starts being dragged around the by the printer nozzle
  • The printer, oblivious of the failure, continues to move around and extrude plastic which begins to build up around the nozzle
  • If left in this state for a couple of hours, enough plastic builds up that it fills up into the printhead and causes significant damage. If however, you catch this failure early enough, you may be able to simply change the hot end (which is a cheap component) and everything will work fine again.

Basically, theres a couple things you can do to try and avoid this in future:

  1. Solve your adhesion issue that started the failure off (this could be due to too high/low a z-offset, poor choice in part orientation, too high or low a bed temperature, poor bed leveling, a draft in the room, contaminants on the print surface, etc.)
  2. Monitor your printer on a more regular basis to try and catch these types of failures before they become significantly damaging
3

Thank you very much for the explanation. It makes sense and fits what I see.

I do pay a lot of care on the heated bed and I level on a regular basis. But draft could be a reason. I will investigate more.

It did cost me a new printer head, an expensive learning point :slight_smile:

Thanks again.

4

You are welcome! Many people in the 3D printing community consider the blob of death as a rite of passage, we are all destined to experience this at some point!

There can be loads of reasons why the print detached so definitely worth investigating. I have a wireless camera on my printer at all times so I can check in remotely whenever I feel like and have the printer connected to a smart switch so that I can also turn it off remotely if required.

5

Amazing :slight_smile:
I will consider this too. Especially the remote switch is interesting.

6

Since you are already getting a replacement, it could make sense to try to salvage the head. At best you have two functional heads, at worst you have a broken but clean head for spare parts/experimentation and the new head. Up to you though!

7

Great thought
 :slight_smile:
Thank you

8

Usually with a heat gun and a little care and patience you can salvage it.
Sometimes the ducting or proximity sensor gets warped or breaks while trying to remove it. But I’ve seen a lot worse than that gets saved.

The other thing that sometimes causes this is leakage around where the nozzle meets the hot end. Generally doesn’t happen with hot end assemblies from factory. Usually when replacing just the nozzle. Need to make sure nozzle and heat break tube make contact, not just nozzle against body of hot end.

-S

1 Like
9

I have indeed managed to separate the PLA from the head.
Not sure if the head still works. We will see. :slight_smile:

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1 Like
10

Thats great, if you swap in a new hot end then you should be up and running normally again!

11

Yes correct. It is working again. Bought a new one for nothing - or spare :slight_smile: Thank you

12

I’ve found the best prevention to drift, assuming the head is calibrated to the bed properly, is a cheap glue stick.

1 Like
13

A very similar thing happened to me. I ordered a new module and before it arrived (took a couple months), I fixed it. I thought I too bought it for nothing. It worked great for a couple small prints.
However, in the process of fixing it, I must have damaged or did something to cause the auto leveler to be out of whack. I still ended up using the new module anyway. C. Harris was right. Filament clogs and jammed filament is inevitable. It’s a perfect example of “don’t ask if, ask when”.

14

Yes, I have the same experience. The auto levelling is indeed broken, or something else is wrong (mis-aligned or something like that). The printer head actually made a dent in the printer bed. :frowning:
I did a manual level though. That worked like a charm so I could indeed use my first printer head, also for larger prints.

Regards,
Bert

15

The bed leveling proximity sensor is located to the right rear of the hot end (if viewed in its mounted position). It is highly likely you blob pushed it up into the print head body. I would suggest removing the right side plate and try to locate the screw that sets the position.

SnapMaker support used to have web page that illustrated the process of recalibrating the proximity sensor but it now seems to be missing. It worked for me, so I hope you can locate the proper step by step instructions.

16

Great👍

I will surely have a look at this. Will be swell to have the old head working again.

Thank you

Regards,
Bert