Ultimaker 2+, extrusion problem

[federico3]

Hi everyone,

Last Friday, I asked you some suggestions about how to improve the quality of a Ultimakers 2+ print… I’ve some good and bad updates about it!

Let’s start with the good news! The project it’s finished and the result it’s pretty cool. Here is a picture of the final lamp:

The bad news is that I didn’t realise what was the cause of the issue. I just reprinted the lamp and, the second time, everything was fine.

"Things will go wrong in any given situation if you give them a chance", Murphy said and, apparently, he was right.

I began a new project with the Ultimaker 2+ but I incurred in a new problem, even before starting to print. When I commenced the new print, I found a “beautiful surprise”. I enclose a picture of what turned out to be the first layer:

Immediately, I thought that there was a problem or with the nozzle or with the filament. So, I cleaned the nozzle and tried again… Same result! I checked the filament and the filament gear: everything was working.

Quite surprised by the situation, I decided to try the “Atomic Test” in order to understand what could have been the cause of the issue. The result was quite strange:

As you can see, the nozzle it’s open. The filament, also, it’s pushed in the correct way. Something it’s going wrong inside the hotend.
tried all the possible temperature within 190° and 220° but the result was the same. So, probably, the issue isn’t caused by a wrong temperature. I checked the hotend and, apparently, there is nothing inside that can block the filament.

Honestly, I have no idea of what can be the cause of the problem: I’d say that is something inside the hotend, according to the result of the tests that I tried but I’m not really sure. Do you have any suggestion about what I can do to solve the problem or to understand its cause?

Cheers,

Federico

[KCT]

Did u check the bowdentube or teflon tube for decay? Or the material feeder could be jammed

[federico3]

Thanks for your suggestions KCT: the bownden tube looks fine. I’ll take a look to the feeder and I’ll let you know!

[alvinlab]

Hi Federico, can you try to use a different nozzle to be sure that it’s not the problem?

[baloe3d]

For PLA I would recommend Tetrahydrofuran, it will clean your nozzle for any left overs. But you might also want to check the health of your isolator coupler (the white part next to the brass tube).

[idamartha]

Can you check the thermistor? It might be not working in a good way.

[Jaime_1]

We have also had similar problems. One solution is to repeat the atomic test until you get a smooth clean result. Also use a filament of another color in order to see the residue that you are removing. We have made a fine metal tool with 0.5mm diameter and made a very sharp tip. We heat up the nozzle to 260 and plunge the tool into the nozzle and work it slowly around the edges of the hot-end. I will send you a picture of our tool later. This should be done with caution in order not to damage the inner tube of the hot-end. You can also check the Ultimaker forum. 3D printing forums - Ultimaker Community of 3D Printing Experts

Kind regards,

Jaime Cavazos

Ultimaker reseller Greece

[federico3]

Hi Baloe3D, thanks for your feedback. The nozzle is super clean, in any case, I’ll consider Tetrahydrofuran for the future.
To check the isolator, should I disassemble the hotend from the printer?

[federico3]

Hi Jaime_1,

Thanks for your answer, I’ll take a look at the ultimaker forum immediately and, if I can’t find anything I’ll make a similar post there. I look forward to seeing the picture of your tool, so I’ll try to repeat the procedure with my Ultimaker.

[federico3]

Hey Idamartha,

I don’t have a thermometer in the lab so, honestly, I can’t be completely sure that the temperature is exactly correct. But both PLA and ABS are melting at the right temperature, so I can suppose that the thermistor is fine

[federico3]

Hey Alvinlab,

I’ll try within today and I’ll let you know!

[SlashDev]

I’ve had similar problems where the thermistor said it was 30 degrees warmer than it actually was. I verified this with an infrared heat sensor. New thermistor solved my problem, probably was a faulty cable.

[federico3]

Ok, I’ll try to buy one during the weekend. In any case, it’s a good tool to have in the lab

[baloe3d]

I don’t have experience with UM2, but it makes sense to remove the hot end to reach the isolator coupler. I have UM1 which should be about the same.

[will_kostelecky]

After you do all the easy checks…like making sure there are no stringy bits binding the filament in the bowden tube, and after checking and maybe cleaning the extruder gear, and trying a different nozzle…I would think that it is likely to be the teflon coupler that needs replacing. They are a consumable item and I have been through a couple.

[MCHD]

Try to put a litlle bit of WD-40 inside the bowden tube, it as solved my extrusion problem with the Ultimaker 2GO.

Regards

Marc

[keebie81]

infrared thermometers will not give you an accurate reading. you need a thermistor to check temps.

[bramthats]

Had same issue, replaced the teflon coupler. That was causing this issue and the problem was solved!
This is wat you need → http://3dsolex.com/teflon-replacements

I replaced it with this one, and the printer prints like a charm

[federico3]

Thanks for your suggestion, I’m quite sure that the Teflon coupler is the problem: I checked everything else and my idea it’s confirmed also by the position of the issue highlighted by the Atomic Test.

[federico3]

Feeder is fine. I’d say that’s the Teflon tube at this point