Very nice design Nitro.

0.5mm should be fine in the frosted ultra detail. At least Nitros 10mm fan came out nice for me. I looked at the accuracy of that process and it seems like the 0.3mm wall thickness is not really a hard limit. They can process clearance of 0.05mm and the accuracy is given as 0.025-0.05mm. This seems to not far from the Plunkett stuff, but at about 1 1/2 orders of magnitude cheaper

Strength wise, the frosted ultra detailed 10mm fan at least survived 110krpm without a problem, I think the material is strong enough, but I know Dave is pushing the limits extremely. So don't forget to wear safety glasses

The point about the 0.3mm thickness limit seems to be that large thin areas can warp, but these very small areas of the trailing edges should be fine in that sense. I bet we could design them down to 0.1mm or even less. The question remains how to convince shapeways to process it, if we take the risk. I really love that shapeways stuff. Nitro really got me into it with his first 10mm fan

Thanks again for your nice work...
Chris
P.S.: I asked shapeways if they would print thinner structures if we take the response, but they won't since broken off parts might mess up the machine.

Anyway, the 0.3mm blades on the 10mm fan don't look bulky. Should be ok and some sanding might help. I wonder if it makes a difference at all in terms of efficiency, maybe a low blade count with with large chord is better under these circumstances. This is what Nitro is going for obviously