Interesting properties of ABS

not only is this material very strong and durable, it is also pretty inert. its a pretty nice plastic. i was reading wikipedia on it and found this nugget:

The final properties will be influenced to some extent by the conditions under which the material is processed to the final product; for example, molding at a high temperature improves the gloss and heat resistance of the product whereas the highest impact resistance and strength are obtained by molding at low temperature.

[en.wikipedia.org]

If that's true... then we could design objects and specify exactly which type of ABS one would like to be printed.

Also, it will be degraded (dissolve) [1] when exposed to acetone. This is already how you clear the etch resist off your pcb. i wonder if we could use ABS as a plastic for printing pcb etch resist!!! if you only clean off the pads, then it would be even easier.

I guess I need to find a supplier that does it for cheap and get some samples.

You are right about about abs and acetone. Here's a website i've submitted on the Make blog explaining how to do it:
[www.makezine.com]

I've made some tests to find if it was possible to extrude abs from a syringe. It's possible, here's a video:
[www.youtube.com]

and a closeup photo:
[www.flickr.com]

Some good points:
-According to the speed of the needle over the paper, you can change the width of the extrusion. Currently, i'm able to achieve 0.5 to 1mm approximately, but by hand it's not easy, as you can see one the video.
-Acetone evaporates quickly, in about ten seconds, then the abs comes back to it's initial rigidity.
-You don't need fancy ABS, a lot of stuff is already made out of abs. In this case, what you see here is part of an old TV enclosure. But i know that black abs pipes do a good job too.
-Acetone is cheap, 8$ canadian dollar for a pint. You can dissolve a lot of abs in such a quantity.
-The dissolving process is easy, throw an abs chunk into a glass jar with some acetone. Acetone will dissolve the abs overnight.
-You can re-dissolve the abs.
-The abs extrusion sticks very well to the previous one.
-Since the ratio of the surface area to the volume of the extrusion it pretty high, the integrity of the extrusion is good. I tried to mold bigger chunks and acetone seems to be trapped inside and some air bubbles are left in the part.
-It does not require heating elements.

Some points that remains to be tested is weither or not you can control the viscosity of the dissolved abs. Right now, the viscosity is somewhere between toothpaste and chewing gum. I'd like to lower it a bit to make the extrusion process less hard on the syringe piston. It tends to buckle a bit.

If you could recover the acetone it might be a good way of recycling plastic into filament feedstock.

Is there a manner to colorize and uncolorize ABS? Doing this, it could get an RGB or CYMK 3D "easy" printer (and also, have a filler head).

See ya! []'s

wow, ABS sounds awesome! i really need to get my hands on some. this is really getting exciting.

LOL! You really need to get your Mk 2 running so that you can extrude plastic, any kind of plastic. Let me tell you, it's quite a rush to watch your very own reprap machine start printing, however awkwardly at first. :-D