It's not relative like that. Measurable results from testing show what processing is necessary for an economically viable part. Turbine blades require a smooth finish after the Arcam build for the reasons I cited previously.
In post #4208, is flying-trader referring to a piece, a bracket, or a turbine blade? What's a piece?
"When Donald Godfrey from Honeywell made his presentation at the last investor's day conference he brought with him a piece they had made via EBM and one they intended to put on planes...
He showed what the piece looked like right out of the Arcam machine, dull and somewhat rough finish, much like the LPT blade shown in that article... he compared that to the one he brought which was bright and polished and said their studies indicated that the part right out of the Arcam machine performed just as well as the bright polished one but that the marketing guys wanted it polished so they sent it out to India to have the post production polishing done..."
If Godfrey said this about a turbine blade, that "their studies indicated that the part right out of the Arcam machine performed just as well as the bright polished one but that the marketing guys wanted it polished so they sent it out to India to have the post production polishing done...," I hope to see his career come to an abrupt and sure end because nothing in metallurgy nor fluid mechanics supports that statement. Brackets on the other hand, well, that's okay so long as it's shown that surface roughness doesn't lead to stress cracks more easily than a polished bracket. As for a piece, maybe those should be made as rough as possible so they don't work. We don't need pieces on planes.
