How would the prints be if your filament had no pigment on the inside?
(edited because I originally said outside instead of inside)
Pla: cloudy and translucent
“Natural” PLA is available, and looks just as @Camerin_hahn describes.
I assume the same goes for ABS.
Natural ABS is more of a translucent white than a translucent clear.
As for your edit, it mixes pretty well in the hot end, so slightly lighter then normal
If you did a very saturated core and natural outside, it would look the same as it would with the same volumetric amount of colourant pre-mixed. As @Camerin_hahn said, it mixes well enough in the nozzle.
Thanks, folk. I had to wonder if it was possible to not color all of it since I thought you might really just see the outside, but I guess I was wrong.
Now that I better understand your question, plastics that are colored using color concentrates are made by mixing pellets of your base resin with pellets of the concentrate. The concentrate is an extremely concentrated amount of colorant often in a carrier resin that differs from your base resin. The concentrates are so concentrated that they typically are added in small percentages. Incomplete mixing of the concentrates with the base resin will result in a very brittle filament.
I have tried mixing some natural ABS and black concentrate pellets in my Filastruder. Unfortunately, the concentrate pellets are bigger than those recommended by the Filastruder makers. The Filastruder does not have sufficient mixing for this large of pellets and I get extremely brittle sections in my filament when using them. I’m thinking about trying to add a small static mixer or something of that nature to mine.
Any reason to not just use the powdered colorants for your extruder? You could get very consistent color and more uniform material.
@Ben_Malcheski thank you for that info. I want to eventually use pellets. Maybe a pellet shaver would help.
@Jonathan_Buford I know some people have extruded natural nylon from powder using the Filastruder. I don’t really see a reason that powder colorants wouldn’t work other than it may tend to fall between pellets in the hopper resulting in a very concentrated amount when initially filling the hopper and less colorant as the hopper empties.
The way that it works in industry, you effectively just shake the colorant with the pellets and it just coats the pellets. The amount is very small and the powder is ultra fine.
@Jonathan_Buford Then I don’t see why it would differ here. I’m not terribly familiar with all of the nuances of industrial extrusion.