LS, or Laser Sintering, Defined
Laser Sintering is a process that uses a laser beam to selectively melt a heated powder. It's done layer by layer, in usually .006'' (.150mm) layers. The process is analogous to Stereolithography, but instead of a vat of resin, there is an exchangeable frame filled with Nylon powder, yet in both processes the material is solidified using a laser beam.
Is it the same as SLS?
SLS, or Selective Laser Sintering, is actually a registered trademark of 3D Systems, and their proprietary process. While similar, the two processes are in fact a little different, the machine we have is made by EOS.
What kind of material is it?
The material is white, called Fine Polyamide PrimePart, aka Nylon 12.
Which is better, LS or SLA?
The short answer is ''it depends.'' Sintered parts will be considerably more durable, and they'll also maintain their material properties long after they're built. Stereolithography parts, or SLA's, will absorb moisture over time, which causes them to expand and become more brittle. SLA's are more dimensionally accurate, and they are the best prototypes for high quality cosmetics, making them excellent candidates for RTV mold master patterns. SLA's can also be polished clear. Sintered parts will have a rougher surface finish than SLA parts.
What kind of accuracy can I expect from LS?
Sintering is not as accurate as Stereolithography. The beam diameter in the sintering machine is about .026'', almost twice the diameter as what's in our SLA machines. Our techs are continually working towards improving accuracy, a process that will continue and remain at the forefront of every build setup (the same holds true for SLA, by the way). That said, in the X and Y axis expect your parts to be +/- .005'' for all features less than 2", and +/- .003" per inch for all features larger than 2". For Z, expect your parts to be within .010'' of nominal in the first inch of Z, with +/- .003''/inch, for each inch thereafter. Holes typically build .010" under nominal, but can be postdrilled as specified by you. For larger quantity orders where multiple runs are involved, we can make adjustments to subsequent runs based on the dimensional feedback of prior runs, to improve dimensional accuracy over time.
Can I paint my sintered parts?
Yes you can. But know that most paints won't stick to Nylon very well, so the paint could rub off even with normal handling. Also, the sintered parts you receive won't have any finishing done to them, so if you're looking for a show-quality prototype for your photo shoot or trade show booth, a better solution is a set of SLA's with a paint ready finish, or urethane castings. But you're welcome to color your sintered parts, and you can even dye them different colors using fabric dye.
Nylon 12 Material Specifications (Click to Enlarge) -Download Print Ready PDF-
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