Shapeways is one of several print services that offer full color prints – something I cannot afford myself. However, they do not allow on-site scaling – you have to scale the model yourself. There are also various cleanup steps that have to happen before shapeways will print your model. For these I use blender. (ref: shapeways page on blender editing)
Scaling, then Lighting, then Checking for Problems
Blender does not (by default) understand units of measurement; however during import, shapeways will ask what the unit is. I go with mm; I want the model to be up to 50mm in size.
The original is starting out at (Dimensions) 0.972 (assumed mm) as its largest dimension. If I scale it up by 50, I get 31 x 48 x 40 instead. Then, very important: apply scale so that the XYZ coordinates are actually changed (some tools, like solidify, work before scaling – used for hollowing out an object).
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Side note if you want to check textures: A this point, the model is a bit dark as the original light is now inside the model, and not quite bright enough. I usually find and drag the Lamp gand drag it out into the open, and give it a distance for falloff of 3000 and more energy.
And now the fun part! Turn on the 3d printing tools (via extensions), and … don’t believe everything. But do check for minimum wall thickness of 2mm. and..
ouch. A lot of stuff. Now, Shapeways may not complain about all of this – you are always welcome to upload. In fact, I’m doing just that, to see what they will come back with.
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Shapeways
False End #1: Do not export as .OBJ. Shapeways does not process the .MTL and the .PNG file, and you get no color. Instead, try .X3D.
If you open the .x3d with a large-text-file editor (like notepad++, or even in blender), you’ll find that it has a reference to a texture file with a different name:
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Be aware of it – zip both the .png and the .x3d file into a .zip file for upload to shapeways.
After the file uploads and gets processed (30 seconds?), you get this screen:
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And if I scroll all the way down, to the interesting stuff – Full Color Sandstone:
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First, $23.13 .. OUCH. Second, Thin walls. It’s a link. Follow the link.
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As you can see, this is not the sea of yellow that we saw earlier. But, it also has this “Fix Thin Walls” button.
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Oh my, we gave Dan the pox. Well, no big deal, lets print that anyway …
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But now we have lost color. No deal. Back to fixing wall thickness in blender (and reducing the size of the model!)