Problems with ColorFabb XT: over extrusion

Question

I could really use some help here. I am trying to print with ColorFabb XT and have been having an overflow problem, which creates an accumulation of material on the nozzle tip creating stringing and depositing random chunks of material randomly throughout the print. When I get the nozzle to 250 °C, the filament flows heavily by itself.

I have upped the print speed, retraction speed and retraction distance and results are getting better, but the problem is still present and my concern is the values are getting relatively high.

I am using a CR-10S Pro and my settings are:

• Print speed: 80 mm/s (I actually started with the recommended settings but they were all off)
• Nozzle temp: 250 °C
• Bed temp: 70 °C
• Retraction speed: 50 mm/s
• Retraction distance: 7.5 mm

I have managed to print some pieces that don't require much traveling since they are round and filament is deposited in a concentric pattern and also each layer didn't use a lot of material but whenever pieces have bigger cross sections and layers need to deposit more material or there is a minimum amount of travel needed, the problem becomes evident.

• Any ideas?
• Has anyone had experience with this material?

Answer 1

Level the bed and check your filament diameter.

Usually this occurs because the space between the nozzle and bed is greater than it should be for the material put out of the nozzle.

Such conditions can happen for a variety of reasons but usually it's an improper bed leveling.

Filament diameter vs what your slicer program thinks is the filament diameter is one of the easier ways to control material output after bed is level. (Sometimes I tell my slicer that the material is smaller than it really is to get it to output more)

Sometimes your z axis moves too much or you are using a layer height that your z axis could not handle. You may have to increase layer thickness.

Getting the temperatures into a point where it is not too hot and not too cold is also important. If the material is too cold, it won't stick. If too hot, it cools and shrinks by the time your new layer gets to it ( making it lower or warped out of place from where the new layer tries to stick ) Increasing bed temperatures is a good way to help counteract the shrinkage.