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

Bronzefill, under extrusion. frustrating!

Recommended Posts


I'm still attempting to get a decent print with bronzefill, and after a couple of really frustrating weeks I thought I was there. Im printing on an UM2 at a temp of 220, with flowrate of 104%, fans of full. Everything goes fine for start of the print and then I get under extrusion for the final 25%. anyone have any ideas? very welcome.

Below is an example of this.

Baby Scan






Share this post

Link to post
Share on other sites

What are the other settings you use?

I don't know if you saw these tips on colorfabb's website:


I used the profile they give for the UM2 and increased the flowrate a bit i think to 107% but not sure about that value. I had no problems printing with BronzeFill but i would recommend to clean the nozzle with the Atomic method between prints to prevent partial (or total) nozzle clog.


Share this post

Link to post
Share on other sites

The atomic method in a few steps is:

- Remove the bowden tube from the top of the print head

- Heat the head to 230C or so (Depend on the clogged material).

- Insert some filament by hand (I often use Nylon or PLA) and make sure you have enough to be able to pull it out later. Use a light color filament to see what comes out.

- If you have a needle or wire that can fit in through the nozzle hole (less than 0.4mm wide) insert it a bit but dont push the inserted filament out. This will help retain the material inside for a better pull and can also help push the clog.

- Push on the filament, reduce the heat to around 90C and maintain pressure on the filament.

- When the head reach 90C pull the filament out.

Repeat a few time if the tip of the filament doesn't come out clean.

Bronzefill is about 5X more expensive than regular PLA so unless there is a real need for 100% infill I really don't seen any general need for that. The material is pretty stiff and 10-20% infill with a thicker shell is mostly enough for bronze even if you polish it.

The 50mm/s in speed I refer to is when printing at 0.15mm layers so you will probably need to print even faster with 0.08mm layers to keep the material to flow.

When polishing bronzefill you can most of the time remove completly the print lines.


Share this post

Link to post
Share on other sites

As pm_dude said i wouldn't print bronze with 100% infill i'd use max 24% if the infill is really needed, if not probably go down to 10% or 0% :)

I don't think it's usefull with bronzefill to go under 0.1mm layers, after cleaning you won't see the lines anymore. Colorfabb's profile for the um2 is:

layer_height = 0.2

wall_thickness = 0.8

retraction_enable = True

solid_layer_thickness = 0.8

fill_density = 20

nozzle_size = 0.4

print_speed = 50


I went with these settings (and adjusted the flow a bit) and it went perfect with no clogs at all.


Maybe try with 0.15mm layers if you want it to be more clean and keep a good speed


Share this post

Link to post
Share on other sites

Yes its the black part on the back of the machine

I have three different models of feeder that I have printed, in fact today I installed one I printed some time ago, I am currently printing my first hand from E-Nable which is about 20+ hour of printing. I had on very large part fail so I decided to changed to the new design extruder and its working like a dream http://www.youmagine.com/designs/2904 the belts give that extra push to the filament.

There are many other designs out there that people swear by too, search youmagine


Share this post

Link to post
Share on other sites

your under extrusion problem could be caused by a number of things, loosening the screws on the top of the print head can sometimes make a difference, just finger tight, the same for the four screws that hold the feeder in place (black bit at the back) in both cases the thinking is that if they are to tight they could cause some distortion which could effect the extrusion. The tension setting on the feeder should be set to minimum - thats the highest position there is a scale visible on the back and side of the feeder.

if the above doesn't fix things then I would recommend removal of the feeder and check inside for filament dust (from grinding the filament)

To remove the feeder you must remove the left white metal cover panel first (single screw on left side of printer) then the four screws that hold the feeder in place as you remove the last on the stepper motor inside needs support or it will drop. Check around the bearing inside the elbow (white piece) for dust, I even lubricate this from time to time

good luck


Share this post

Link to post
Share on other sites

I'm still not sure what it is I'm doing wrong. I've done all of the settings as mentioned but am still getting under extrusion, with the annoying clicking sound as the material is failing to feed.


Hi Dave,

I think the problem might be your model is really tiny. This probably means the minimal layer time will determine the max print speed and not the set 50mm/s.

Now when the print speeds slows down the filament will move even slower through the hot-zone, allowing heat to migrate through the filament. This can cause some issue with the teflon coupler, especially if it's already worn down. Have you every replaced the white Teflon coupler?

My tip for printing this specific model would be to print maybe 2 at a time, or increase the scale. Both options should result in faster printing.

Another way could be to adjust the minimal layer time down, so it'll allow for the 50mm/s. But if your model is too small it can't cool down.


Share this post

Link to post
Share on other sites

Thanks everyone. I've now managed to print a successful bronzefill model (taken from thingiverse). I reduced the infill to 20% and put the speed up. I gave the nozzle a very good clean out before printing and everything went fine. Pics below.

Once print was finished i sanded back with wet and dry, then used a wire brush, then scotch brite, then final polish with wire wool and brasso. Once dried i then treated the model with gilders paste before giving it a final polish.

DSC 2073

DSC 2070

DSC 2068

DSC 2067

DSC 2066


Thanks again everyone for the help.




Share this post

Link to post
Share on other sites

.......... I am curious though as to how a bronzefill print sounds when it's dropped? Metallic at all or still pretty plasticy?


It has a metalic sound when knocked against a desk for instance, its a lot heavier than plastic,but it is more brittle just had a piece break in half never happened with the same item in regular PLA

still it looks great when polished up


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

    • Ultimaker Cura | a new interface
      We're not only trying to always make Ultimaker Cura better with the usual new features and improvements we build, but we're also trying to make it more pleasant to operate. The interface was the focus for the upcoming release, from which we would already like to present you the first glance. 
        • Like
      • 79 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!