Print head clogged up UM3

[joakimnorman 0]

Hi! I've had an unfortunate incident with my UM3. The filament didn't stick to plate and instead started gathering around the nozzle. Eventually it crept up into the print head itself and now basically the area inside the print head, in and around the print cores, is filled with solid PLA.

I'm trying my best to get it out but I'm guessing I'll have to try and replace the print head after I've gotten it all out. I can't really imagine that this hasn't affected it printer in some inreversable way.

Has anyone else had this happen to them? Is it possible to buy a replacement print head? I can only find replacement print cores on the website.

Grateful for any help.

Joakim

[gr5 2,094]

This is a common problem and the entire reason why the head has that white silicone damn. If you can't get the door open it's going to be tough. I'd start by heating the nozzles to 160C and then getting a hair dryer or heat gun and carefully heating up the bottom of the head until you can get it open. Then just be patient. It can take an hour.

In the future learn more about how to not let this happen ever again:

 

[ultiarjan 1,223]

for the Bill of materials and UM3 CAD model;

https://github.com/Ultimaker/Ultimaker3

The CAD model (.stp file) can be helpful to see in detail how the head is assembled.

This re-seller has all spare parts picture books on its website, links in the middle of the page;

http://www.mindkits.co.nz/bearing-housing-middle.aspx

You can order every part at ultimaker re-sellers, even though most don't have them on there webshop, just mail them.

If you're not confident about taking stuff apart yourself have your re-seller do it for you, they have done it before.....

[Oj00 5]

Hi Joakim,

Ultimaker are going to hate me soon for keeping posting this image, but this failure has occurred for multiple people. Our failure:

With this we were able to clear it out, and the fans were unaffected, also the print-cores, once heated to soften the plastic were cleaned and we are still using them. They seem to work fine still.

We did replace the print head on ours, but that was due to other damage and failed bearings. Your print head will probably be okay, so long as you clean it out and disassemble it carefully.

[gr5 2,094]

So "normal" leveling techniques leave things so that the above is common. But I have never had this problem and I've been printing for 4 years. Thousands of prints. My secret - get the part to stick like hell:

[Brolman 0]

After 7 months and more than 2000 hours use, I recently experienced a similar horrible printhead clog  with PETG which is unbelievably hard to remove. That jam damaged the printhead as well as one of the printcores.

I contacted my local reseller, and bought a new print head to replace the damaged one. I firstly recalibrated the printer.

The first prints were perfect. So after two days I tried to print overnight but  I had to face the same experience with the new print head (dead also). Please dont tell it is normal because, obviously it is not. 

I am quite disappointed by Ultimaker by now. 

I don’t trust the printer anymore. I doubt the printer is still reliable. It cost me two printheads and three printcores in two weeks….

[gr5 2,094]

It's NOT normal.  It's just a common problem because people don't know how to get their parts to stick well.  I did experiments with many variables (temperatures, glues, glue thicknesses, squish amounts).  Not everyone should have to do that.  That's why I made the video - to help people understand how to get the parts to stick like hell.

 

The steppers should skip before the part comes off the bed.  The part should never come off the bed during printing.  Even with 2000 hours of prints.  It should be that firmly attached.  In particular with PETG I go a little too far sometimes and pieces of glass end up inside the bottom of my print.  The key missing piece is usually to squish your first layer more into the glass.

[FraggleRock 4]

It happened to me as well using eSun PETG. The settings for this material were perfectly dialed in, but the problem is I forgot to spread some glue stick on the glass. This material does not adhere to glass very well. My bad!

Instead I left it on it's own for hours and came back to a clogged printhead.

Wires were pulled off their connections as well so it wouldn't heat anymore! That made it super hard to clean.

Eventually after hours of using a solder iron the best I could, I removed every trace of it out of the printhead, and was able to pull the nozzles out. In the end I had to use the 2nd nozzle until I figure out how to fix the one with the cut wires.

Anyone knows how to re attach the nozzle wires back to it's circuit? They look like crimp connectors. I can't really tell.

[AndersK 59]

For anyone struggling with bed adhesion I would recommend using PEI sheets.

Since I got my BuildTak flexplate system with pei there has been not the slightest issue.

 

Printed pla, petg, tpu, carbon fibre filled nylon and petg it all works without anything extra on the plate. Pet is also fairly easy to get loose when finished.