This is the first I heard that an Aluminum Injection Mold can't produce a smooth part.....
That's not what I said. The reference was to silicon molds, which in fact do shrink and peel, especially with multiple uses. Never tried aluminum injection molds, so I can't say how well they work (though I asume it would be fine, since that's how some plastic parts are originally created)
... perhaps you are talking about STL or another form of 3D Printing?
STL is a file format for 3d models. They get sliced and turned into machine commands for a 3d printer.
3d printers do an acceptable job of producing parts, but they too have to be cleaned up and finished.
Not to mention, they take a long time for the actual printing.
Rapid prototype stuff will have sand paper texture that will require 100 hours of polishing and sanding and painting to approximate the original. Additionally, its going to be fragile at the hinge. Even installing it without breaking it could be tough since it has to be squeezed a bit.
The finish can be done in less than 1/2 hour. It does not require 100s of hours of polishing, etc, if you are working in ABS plastic. 5 minutes or less in an acetone vapor bath, plus time to dry.
Anything you make is going to be fragile at the hinge joint. The little nubbies are prone to breakage, no matter how the part is made. ABS is a bit more forgiving than some of the harder plastics, though. Like I said before, its a bit more flexible.
I deal with RP parts at work quite often and you have to be really careful with the stuff.
What kind? Sintered metal? Fused thermoplastic? Something else?
Yes, rapid prototype parts can be breakable, depending on how they are made. That does not mean they have to be, though. Done right, small runs can be as durable as the orginal - it is just plastic. Injection molding does not change the plastics properties.
And just for the record: there are several kickstarters gong on right now to produce a filament making machine from raw ABS pellets and colorants, so people are no longer limited to the 'stock' colors. Someone with a good eye for color could probably match the slight purple tint the Duo-R has.
[on a personal note: I'm Cheap. ABS filament is ~$50 for 2Kg, which would probably be more than enough to make 20 doors. If you go the color-your-own filament route, it costs about $10 in materials to make the same 2Kg, since raw pellets are cheaper. Maybe I'll steal Arkhans door and model it, just to see...]
