Thinking about mixed material printing reminds me of the ink pen plotters of old

Thinking about mixed material printing reminds me of the ink pen plotters of old where the pen carriage would retrieve different pens during a plot. Aside from programming the plot why not a mechanism to put and pick extruders from the end of the carriage ?

well, or just take the easier route of marrying an inkjet cartridge array to the intake of a single extruder – that has worked fairly well for some folks (though the colors are more muted).

Separate extruders could have differing material either type or colour.

@Matthew_Griffin does that technique allow you to print objects in full color? Could you print a graphic like a halftone on (or in) the material?

That was the originally intended method with the Darwin Machines - they thought the top bar could be used to house heads. The biggest problem with the idea, and the reason it was abandoned, is calibration. Reprapped components don’t tend to have the sort of absolute precision that would allow multiple different heads to work with identical calibrations.

Thanks for the history lesson … I am New to this ! I can see that it would become a nightmare to calibrate at this level of detail … those old plotters looked sharp but they were using “Sharpies”

@William_Frick I know your point was multi material but the subject of color was intriguing. Anybody using this set up? Thoughts? http://richrap.blogspot.com/2012/08/3-waya-quick-fit-extruder-and-colour.html?m=1

Dead link for my @John_Hauer . Googled it and got this page: http://richrap.blogspot.com/2012/08/3-way-quick-fit-extruder-and-colour.html

Looks like you posted the mobile page and when i click for the web version it doesn’t work.

Anyway, I doubt many people have that going because the hotend was very kludgish and it needs a controller with 3 extruder channels.

However, RUMBA has 6 stepper drivers, and I’ve got one coming in the mail, so I might end up toying with that design this spring.