ttabbal wrote:I'd be interested in trying some metalics etc.. Not sure where one would get suitably fine wood dust, metals are easy enough though. Any particular reason to want to try with PETG? Just curious. I would need to get a bigger nozzle for the printer, but that shouldn't be too difficult.
For the filastruder, could one use a larger filter screen? Something like 0.7mm for a 0.8mm printer nozzle... That would likely not work so well with glass fiber (or carbon fiber), but for fine metal powder it seems like it would work.
Revolve3D: I'm interested in pricing for PETG as well. Is the vacuum setup really required to dry it?
I make my own fine wood dust with this http://www.thingiverse.com/thing:724999, so that would actually be the easiest/cheapest additive for me to try. Plus, I could try all kinds that way - poplar, oak, pine, and under no circumstances incense cedar (I already hate the smell of that, before heating it up to plastic extrusion temperatures).
You could probably even get away with using the filter if you get a sufficiently fine metal powder - the filter is 250 microns, that equates to a #60 mesh (mesh size is inverse, so if something is stated to be 325 mesh that's actually much smaller than 60 mesh, but if it's rated at 30 mesh then that's much bigger than 60 mesh), so if you get something that is 99.6% -325 mesh then almost all of it would go right through the filter, and then you could just have the filter do it's job and block the larger pieces.
I'm personally interested in PETG because I've printed parts in PLA/ABS/PETG/Polycarbonate (and attempted in POM - ugh, polycarbonate is much easier to avoid warping than POM, hated POM) in PLA the part - snapped without signs of stress, ABS - snapped after being under load for a bit, polycarbonate - held together with no sign of failure, but was not rigid - it flexed too much, PETG - held together, and didn't flex. So for me - it's the strongest under the use cases I have had. PETG also has amazing adhesion - I have a chuck of glass missing on my first printer because it stuck to that glass that much - and the glass was a permanent part of the bottom of that printed item - it never would come off. Sure, that can be a disadvantage to say the least - but as long as you do something like use blue painters tape (the tape loses adhesion to the glass before the PETG eats your glass bed) that disadvantage becomes an advantage.
You just have to dry it REALLY good (I've read at least) to avoid air bubbles in the middle of your filament (that would cause stringing and layer voids later). Your way of doing that is up to you. I personally like vacuum because in a perfect vacuum water boils at 70F. That means if I heat PLA right up to 55C, then put it in a vacuum dessicator, it pulls all the air out of there, I will have a white mist coming out of the pump - water vapor - actual water coming out of the filament and turning into a gas. Then, I can just close the valve, and it'll stay dry until the time I need to use it. All without heating the plastic up past it's Tg and deforming it. Which I guess is probably more important when you're trying to dry filament than it is when you are just trying to dry some pellets.
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Seems like a good way to try out the process and see how I like it. Interesting side use of it, making wood dust for filament. 