cvrnd
1
Hi,
I have sometimes problems that the Woodfill from Colorfabb gets stuck in the nozzle at an Ultimaker 2. Today I was away for ten minutes and only some kind of oil was drupping out of the nozzle. See images attached.
Everything ended up fine after several times of cleaning with the atomic method but what can I do to prevent the nozzle to get blocked?
3 Likes
What Temps, speeds, layer height etc are you running? do you have extruder/spooler upgrades? how many hours on PTFE insulator? is it only woodfill you have a problem with?
So many questions…lol…
Xeno
3
Woodfill cannot be left inside the nozzle at temperature for long,
best is to remove after using it, and extrude another kind of filament to clean the nozzle.
it burns fast 
2 Likes
MB3D
4
You can also add a custom gcode at the end of printing, this could include a retraction of a.e. 30mm. So you get at least most of the WoodFill out of the hot nozzle. Also a larger nozzle diameter might help, as the fibers can cause extra resistance in the bowden-system, when they barely fit through a tiny nozzle. Cheers, Marius Breuer
1 Like
We had exactly the same problem on our Ultimaker 2 and Woodfill. Ended up buying a new nozzle because our prints kept getting ugly/bad results with other materials after the woodfill.
Most important: Turn off retractions. Keep it flowing. Retractions lets in air and the water in the filamenet vents away. Woodfill 125-135% material flow. It is right what the others say, bigger nozzle helps and also looks beautiful, but is not strictly necessary.
First layer 220C to make it stick, then lower to 210-215.
An Olsson Block with exchangable nozzle helps.
2 Likes
Make sure you print quite fast. at least 50-60mm/s at 0.2mm layer (100-120mm/s @ 0.1mm layer). If you go below that volume (4-5mm3/s) you are likely to have progressive clogging.
Make sure the minimum layer time will not interfere with this speed.
2 Likes
cvrnd
8
Thanks for the advice! It is now already printing well for 4 hours. So probably the advice of Xeno, cleaning the nozzle now and then, is worth a try! And I will play a bit with the retraction length!
for your interest: 210C, 110%, 60m/s, retraction normal.
We had the same issues with woodfill and clogging, and despite all changing the temprature, printing speed, insulator and more, we couldn’t get reliable results with woodfill on print jobs longer than 1 hour.
In the end we switched to an olsson block, with 0.8 brass nozzles, and so far it has worked like a charm. It takes some trial an error to get the settings right for printing with woodfill in a 0.8 nozzle, but we got much better results.
Here’s the link to the olsson block & jet nozzles: http://3dsolex.com/.
We got near perfect results with these settings:
Temp: 205ºC
Speed: 50mm/s
Layer height: 0,15mm
Retraction: 3,5mm - 45mm/s
Z-hop: 0.1mm
4 Likes
fiilo
10
We have had the exact same issue with the bamboo fill from Colorfabb and our Ultimaker 2. We have stuck to the recommended settings but only managed one quick successful print with it. Shame as its rather expensive. Not sure what to do with it!
Hi!
It seems to me that the residence time of the filament is too long in the heated zone of the printer, causing too high of a heat to the wood particles in the filament. Colorfabb talked about residence time last time they vistited 3d hubs eindhoven, explaining that the mm3/sec is the crucial parameter in printing. in this case, perhaps even increasing the printing speed will cause the filament to have a shorter residence time in the hot-end.
What have you tried so far?
Cheers!
Hi,
All the wood, bamboo or similar filament types are quite prone to clogging. The problem stems from the woodfibres which are part of the filament and which have problems getting squeezed through nozzles of .04mm and less. Ideally, you should use at least a .06 or even a .08mm nozzle, as that removes most of your problems. I am printing with the stock issue .04mm nozzle on my Ultimaker Original and did not have a lot of problems with it.
But when I tested Laywood (the first wood filament to hit the market), I also found some other issues I have written about on my blog. The main issue arises when you keep those types of filament at high temps in the heat chamber without actually extruding any filament. This results in burning the filament, which in turn WILL clog your nozzle more or less completely with solid carbon. And there is not more serious pain to remove from a nozzle than those carbon remains. Most people just give up and replace the nozzle.
The solution to this issue is purging your heat chamber immediately after you are finished printing: just install a roll of PLA or ABS (whatever is your favourite), heat up the hot-end to 250°C and extrude at least 100mm if not more of that filament. This purging normally cleans out all the remaining fibers. If you use some white filament, you can see well how long it actually takes before it is completely clean again. Some may consider this a waste of good filament, but I prefer losing 100-200mm of filament to the cost of replacing a nozzle!
If you are interested to get a bit more into those issues, just check out the Laywood section of this article: Advanced 3D Print Materials Analysis - BendLay, Laywoo-D3 and LayBrick | 3D Printing for Beginners
Mich
3dprintingforbeginners.com
same problem, each print nozzle is blocked, I gave up the use of this filament
Hi all, I’ve done some testing with both WoodFill & BambooFill, as well as a little bit of printing.
1st Nozzle Temperature, print at as low a temperature as you can sticking to the lower limits.
2nd Feeder Pressure, ease offf on the applied pressure on the feeder, I would recommend Roberts improved feeder as this is easier for filament changing and for adjusting the pressure of the feeder on the filament especially for softer filaments that are prone to squashing.
3rd Retractions, I have found that a lot of retractions similar to the feeder pressure can result in squashing the filament, this will seem to feed fine through the Bowden tube but will jam up against the coupler and stop feeding through.
I have done all my testing on a 0.4mm nozzle and the latter tests using the Olsen block and nozzles, I would recommend a slightly higher 205-210’C and 0.2mm layer height for the first layer the reduce the nozzle temperature for the rest of the print, I have printed at 0.1mm layer height and even 0.05mm with care for a small print.
So as not to keep the filament in the nozzle at run temperature for long, I would recommend using maintenance to heat the platform up to temperature first, if you then heat the nozzle to 190’C to manually load the filament (it will just push through at 190’C)then start the print, as the platform is at temperature it is just waiting for the nozzle to reach temperature and start quickly.
When the print finishes, manually retract the filament back out of the nozzle.
if you have the wood addin for Cura you can vary the temperature a few degrees for a layer or two to obtain a grain effect.
Its worth persisting with for good prints.
Izzy.
1 Like
gr5org
15
Hi @Mark_43, good to hear you’ve been paying attention during workshop Residence time is indeed key for 3D printing, many issues can be explained by residence time alone.
Keep trying don’t give up. It’s a more challenging material for sure, but you’ll be rewarded with very cool looking prints. You can also contact us at support@colorfabb.com.
@cvrnd how is the print going? Did the tips below help get better results?
