It occurred to me that we could colour the plastic after a layer has been deposited. Either use a "Unicorn"-type pen holder to colour the surface/edges of an object, or a whole inkjet head to spray on a layer of colour from above. Add another translucent layer of plastic and re-colour. Rinse, repeat. Any takers? Vik :v) https://reprap.org/forum/read.php?2,103131,103131#msg-103131 Sat, 11 Jul 2026 16:10:13 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?2,103131,106626#msg-106626 https://reprap.org/forum/read.php?2,103131,106626#msg-106626
Pre-print.. CMYK pigments (powder and a custom binder? Or acrylic?) feed into as many plastic syringes as you need colors in your print.. let's say four.

During print, one peristalic pump drives a hose from each syringe and releases the droplets of color over a compressed air source. Use solenoids or a cam to unpinch/select the color you want. I think you would want to print a compressed air nozzle that shielded/directed the spray appropriately. Maybe a donut shape that surrounds the extruded plastic? Ideally you would mix the PLA and the color pre-extrusion in a screw-type mixing drive.. CMYK powders and PLA granules.. but that sounds incredibly messy and I believe that high temp is going to be an issue for many pigments.]]> jason.fisher Developers Thu, 17 Nov 2011 19:56:44 -0500 https://reprap.org/forum/read.php?2,103131,106588#msg-106588 https://reprap.org/forum/read.php?2,103131,106588#msg-106588 -------------------------------------------------------
> How about a multi headed extruding tip that can
> feed 3 different colored
> filaments(blue,green,red) through the same hole at
> once ?
> Tricky to build I know, but you could have each
> filaments extruding at alternate speeds to create
> different colors.
> I guess it would also be a huge task to change all
> the software to run it also.
>
> Ignore this post if to far fetched >.>

I'd hate to have to clean such a beast ;-P]]> raldrich Developers Thu, 17 Nov 2011 16:19:24 -0500 https://reprap.org/forum/read.php?2,103131,104689#msg-104689 https://reprap.org/forum/read.php?2,103131,104689#msg-104689 Tricky to build I know, but you could have each filaments extruding at alternate speeds to create different colors.
I guess it would also be a huge task to change all the software to run it also.

Ignore this post if to far fetched >.>]]> Spenc Developers Fri, 04 Nov 2011 05:06:46 -0400 https://reprap.org/forum/read.php?2,103131,103292#msg-103292 https://reprap.org/forum/read.php?2,103131,103292#msg-103292 www.kickstarter.com]

I have one coming my way, and sooner or later it will end up on a reprap of some sort.]]> DeuxVis Developers Wed, 26 Oct 2011 08:24:29 -0400 https://reprap.org/forum/read.php?2,103131,103233#msg-103233 https://reprap.org/forum/read.php?2,103131,103233#msg-103233
With changing the material or colour per layer or even inbetween a single layer (by exhausting the previous powder and filling the actual layer with the new powder) you can print all imaginable combinations of mixed materials (plastics, ceramics, metal, wood/lignin, ...) and/or colours.

So my aim is a powder bed fitting to my repstrap and changing the firmware for handling the layer-changing ...]]> VDX Developers Wed, 26 Oct 2011 03:19:35 -0400 https://reprap.org/forum/read.php?2,103131,103210#msg-103210 https://reprap.org/forum/read.php?2,103131,103210#msg-103210
Might have to play with unicorn pens. In theory you could see what this looks like by following your printout around with a sharpie :) But it allows a relatively simplistic build, which I like.

Vik :v)]]> VikOlliver Developers Tue, 25 Oct 2011 20:49:52 -0400 https://reprap.org/forum/read.php?2,103131,103183#msg-103183 https://reprap.org/forum/read.php?2,103131,103183#msg-103183 That way, the color would be spread relatively uniform in each 'blob'.

Alternatively, in what way do the colors of different fibers mix? (Probably additive, but we're definately not geting something as simple as RGB or CMYK).
Could we get away with building a three/four color extruder that controls the color being dispensed by the proportion of different filaments?

If mixing colors is not an option, we might at least be able to add more white for lighter colors, allowing us to print in shades.
In fact, this might be a good option to start with, expanding to color mixing later.

Edit:
Just found this on thingiverse: [www.thingiverse.com]]]> SarahMiller Developers Tue, 25 Oct 2011 17:07:59 -0400 https://reprap.org/forum/read.php?2,103131,103143#msg-103143 https://reprap.org/forum/read.php?2,103131,103143#msg-103143
for the rough surface of a layer an ink-jet head will be better than a sharpie, even when it's supported by a spring.

Points to a two-head printer ...]]> VDX Developers Tue, 25 Oct 2011 15:50:52 -0400 https://reprap.org/forum/read.php?2,103131,103131#msg-103131 https://reprap.org/forum/read.php?2,103131,103131#msg-103131 after a layer has been deposited.

Either use a "Unicorn"-type pen holder to colour the surface/edges of an object, or a whole inkjet head to spray on a layer of colour from above.

Add another translucent layer of plastic and re-colour. Rinse, repeat.

Any takers?

Vik :v)]]> VikOlliver Developers Tue, 25 Oct 2011 15:23:20 -0400