Jump to content
Ultimaker Community of 3D Printing Experts
Sign in to follow this  

Problems Extruding with New Ultimaker 2

Recommended Posts

We got a new Ultimaker 2 a week ago. After some tuning, we were printing successfully and put between 50-100 hours of print time on it

This morning I came in and noticed the extrusion was looking spotty. Here are some pics to clarify:





It's printed nothing but PLA so far. Any tips to help fix it?


Share this post

Link to post
Share on other sites

It is under-extrusion:

The problem can have many causes:

- Have you tried other materials?

- Try to optimize the material supply, so that it can be fed straight as possible without angulation.

- The material should be easily unwound from the roll.

- Have you thought of printable material Guides?

- If a dust filter before the material feeder?

- Filaments can have external contamination.

- Sits the Bowden still correct in the two couplings?

- The Bowden-end to the print head needs to sit directly in the cold end.

- The cold end is that white and round plastic part (Teflon) visible at the front of the printhead.

- Are filament crumbs, or other impurities in the Bowden recognizable?

- Sits the knurled wheel on the rear feeder yet firm enough on the drive shaft?

- It could be a partially clogged nozzle, there are many solutions with varying levels of success.

- An injection needle with 0.4 mm outer diameter is a useful tool.

- The Print-temperature at the selected speed may be too low.


Share this post

Link to post
Share on other sites

Thanks for the help.

We cleaned out the nozzle with a guitar string (bit of gunk in there) and dusted off the spool with an air hose. It's extruding fine now. Thanks again.

On a different note, anyone know how to lower the default bed temp so PLA prints don't keep warping?


Share this post

Link to post
Share on other sites

Well, that lasted about a day. After getting some smooth prints out of it, it's back to under extruding.

Tore, I'll give that a shot, but there has to be a better way. It's frustrating to see our original Ultimaker sitting right next to it doing fine. Has anyone else had under extruding issues with the U2?

For Mnis' suggestions, we've only used PLA, but we've tried it from various suppliers with the same result.

We're using the feed guide on the machine, and the tube seems seated well in each end.

We just cleaned out the nozzle. Nozzle temp is 210 with bed temp at 60.

I'll give adjusting the pressure on the extruder wheel a try. I'm open to other suggestions as well.


Share this post

Link to post
Share on other sites

The contact pressure (Material-Feeder) increase only slightly, and see if it does what.

It is often not advised to do this, which is even in the Manual (UM2). Usually you do not succeed, because eventually the motor does not have enough power. But an attempt not hurt.

A better way is to find out whether the bottlenecks are in the area of the print head.

Printing with a somewhat higher temperature (215-230) degrees and lower speed 30-45mm / s, can miraculously help alleviate the problem.


Share this post

Link to post
Share on other sites

No luck adjusting the Material Feeder pressure, any change seemed to make things worse.

We cleared out the printhead twice, so unless the bowden tube shipped full of sand I think we can rule out bottlenecks.

Printing with higher temp might help for a while, but if we have to crank it up every print then it's not a very good solution, long-term-wise.

Has anyone else had underextruding problems?


Share this post

Link to post
Share on other sites

Under extrusion and burying the knurling wheel can have so many causes. Many UM2 machines run, apparently without problems. Some machines run only at the beginning without any problems. Still other machines prepare problems from the beginning.

Many problems are also directly related to the material used, which makes it difficult to troubleshoot.

I think: If there are many problems with the machine and the original material from Ultimaker, then the manufacturer to repair the machine should necessarily first be asked.

Some UM2 users increase the power of the extruder motor using an optional entry in the G-code files. That should help in some scenarios already to eliminate the Under-extrusion. I would then additionally use the adjustment screw for the back-pressure role.


Share this post

Link to post
Share on other sites

Several users have had under-extrusion issues, but many have not. Ultimaker is aware of the problem, and working on fixes from several angles.

In the mean time, see this thread, and try the extrusion test:


One thing that can cause issues is having tightly wound filament - particuarly as reels are depleted so that you're using the more tightly wound plastic closer to the core. For best results put the reel on the floor, and pull of plenty of loops hanging in the air, so that the feeder doesn't have to work hard to pull the plastic off the reel.


Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Our picks

    • How to 3D print with reinforced engineering materials
      Ultimaker is hosting a webinar where we explain how you can achieve and maintain a high print success rate using these new reinforced engineering materials. Learn from Ultimaker's Product Manager of Materials and top chemical engineer Bart van As how you can take your 3D printing to that next level.
      • 0 replies
    • "Back To The Future" using Generative Design & Investment Casting
      Designing for light-weight parts is becoming more important, and I’m a firm believer in the need to produce lighter weight, less over-engineered parts for the future. This is for sustainability reasons because we need to be using less raw materials and, in things like transportation, it impacts the energy usage of the product during it’s service life.
        • Like
      • 12 replies

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!