Hi Marco!
Here are a few answers I can provide:
A) For exporting from Moi, which format I must use : Obj or Fbx or others ?
— Most print services can handle a range of formats, but keep in mind that STL does not contain color information. For full-color 3D printing I usually use embedded vertex colors in the mesh, exported as WRL (VRML2) or X3D.
B) Can I export the model directly from Moi in high-poly version (with the export dialog of Moi) and SEND IT DIRECTLY to the printing service without doing any kind of tweaking ?
I mean, without dealing with "normals" or any other kind of "inside" aspects ?
If I export in this way the 3D Printed object will be smoothed or it will be faceted ?
I mean, if I export a curved solids from Moi, in high-poly version, that area will be "smoothed" into the 3D printed model ?
— A 3D-print model is always polygonal, except when you use CNC milling techniques I believe. This means it will always be faceted, because a smooth appearance of a mesh is a shader-based rendered illusion. Therefore it is advised to keep your poly count high for smoothly curved 3D-printed surfaces.
— Also very important: make your mesh hollow, with a thin outer wall, before printing it or having it printed. That will keep the material volume low, resulting in a much lower price than printing a fully solid model.
C) In the same way, can I export directly from 3D-Coat a voxelized model having millions of polygons or I have to "decimate" it before sending to the printing service ?
Also, same considerations about "smoothed" area of the objects...
— Last time I checked it, the Shapeways printing service can handle a maximum of about 1 million polygons, so sometimes decimation is needed. But maybe the maximum polygon count has been increased in the mean time.
D) Do you know a good 3D printing service that I could use to make some test ?
Please consider that I don't want to print many pieces but only a very limited amount of pieces (1, or 2-3 for each model and anyway less than 10)
— I'm content with Shapeways, but for more affordable printing you can try a local print hub service, such as
https://www.3dhubs.com
— Here's my Shapeways shop:
https://shapeways.com/shops/sevensheaven
Have a nice weekend,
Metin
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visualization • pixel art • illustration • 3D design —
https://metinseven.com