Most 3d printers like my machine use filament there is also other 3d technologies available that use liquid resin and even metal powder, but the more affordable printers use plastic wire wound on a spool.
I got a great deal of some filament (the plastic on the spools) but I got rolls that don't come with spools, thats not a big deal as you can print a spool and reuse it instead of creating lots of waist with used up spools.
I printed a bunch of these reusable spools and was printing with my new color mixing printer when I realized something really awesome about it, and although its not quite the type of dual color printer, I wanted a printer that had 2 heads but the printer I got only has one head and the 2 filaments go into it, and you can choose which one you want to use or even a combination of the 2.
right below is a gif of the printer mixing some clear plastic with some black the clear plastic is coming at 95% and the black is coming in at only 5% you can see how the right side (clear plastic) gear is moving fast while the black is barely moving.
and the result is a black looking spool, the one in the front of the pack is a 95% transparent and 5% black and the other 2 are pure transparent and pure black, as you can see the one that only has 5% black is pretty dark and looks almost like the fully black one with an added shine, this method is great as I barely used up any black and this can come in handy because some colors are more expensive and with this method you can save expensive filament with mixing.
Hope you got some value from my post,
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