I am sure it is by weight. Typically, plastic spools go for around $18-35/kg. Every company seems to shy away from guaranteeing length. But, if you know the volume of the part you want to build, it is almost a 1:1 transfer of material.
Lulzbot says, "The LulzBot AO-101 is one of the few desktop 3D printers on the market that can print with ABS and PLA plastics. With some simple adjustments, you can print with a wide array of experimental materials like wood filament, nylon, polycarbonate, polystyrene, and glow-in-the-dark materials. "
I am sure they will have to verify the type of materials first. So, I don't think this will be printing stainless steel from spools any time soon.
The Business Advantage Group recently released its 2014 Worldwide CAD Trends Survey, announcing both a prospective increase in the cloud-based CAD industry and the anticipated incorporation of 3D printing.
Autodesk, a leader in 3D design solutions, announced earlier this month that it has completed its acquisition of Delcam, a leading supplier of CAD/CAM manufacturing software, in its efforts to expand the company’s manufacturing software capabilities.
Texas Instruments' Webench is vying to win the Golden Mousetrap Award in the Analysis & Calculation Software category, but it is up against some pretty tough competition from Mentor Graphics, COMSOL, and aPriori Inc.
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