Tips and Tricks for Flex filament

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Tips and Tricks for Flex filament

Postby RetireeJay » 2016-Aug-Sun-20-Aug

Anyone who has anything to add, please feel free to chime in!

I was trying to print an accordion-like bellows, and kept on having problems with inter-layer adhesion. The slope of the walls was 45 degrees. When I looked closely at the bellows, it looked like I was under-extruding because there were tiny gaps. I was using a 0.8mm nozzle and 0.6mm layer height, and the walls of the bellows were 1.6mm thick in the X-Y plane (two traces). I finally figured out two corrections to make:

(1) My layers didn't have enough overlap from layer to layer. When I decreased the layer thickness to 0.4mm, the quality improved dramatically - although still not quite good enough. At this layer thickness, with 0.8mm trace width, and 45 degree slope, the overlap on the overhanging layer was 50%.

(2) Because the printed object is so flexible, it was deflecting under the pressure of the material being extruded, reducing the ability of the new layer to weld to the previous layer. So I increased the Extrusion rate in Slic3r to 1.12, and also after the first 5mm or so had been printed, I increased the Flow rate in Repetier to an additional 15% (for a grand total extrusion of 28.8% extra material). This actually worked very well - there were no signs of over-extrusion, the walls were very uniform and completely filled, and the finished product has very good inter-layer adhesion. When the print reached the top of the bellows and started doing some less-flexible layers, I dialed back the Repetier flow rate to 100% or even a little below to prevent "bulldozing" and over-pressure in the extruder.

It's really amazing how good the inter-layer adhesion can be when using Ninja Flex Semi-Flex!
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Tips and Tricks for Flex filament



Re: Tips and Tricks for Flex filament

Postby plexus » 2016-Aug-Mon-11-Aug

Very interesting and useful info! When ninjaflex bonds, it really bonds! its more like a sticky rubber than a plastic.
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