Thanks to Stepan83 for the Elviolin.
http://www.thingiverse.com/thing:745940
its design has inspired me.

In this version:
I modified some parts to facilitate printing without supports
I have given a different and modern look.
And I've added a integrated chinrest support.

All parts can be printed without supports, except for the chinrest

Recomended printing parameters:

5 Shell thickness.
4 top down solid thickness.
20 to 30 % infill
0.20mm. layer heights.

If you print on ABS filament, you can use acetone or PVC pipe glue to bind the parties. If you print on PLA, then use a epoxi glue.

You can use a sanding papper and patching paste for automotive jobs to leave a smooth surface to paint on color of your choice.
Dont forguet to use a primer paint before the application color.

you can find on ebay the electronics.
Find as electric violin pickup.

Use a 9.5mm threaded rod as steel core to stronger the violin body.

Instructions
http://www.thingiverse.com/thing:745940/#instructions

materials list:
Printed parts - 6pcs
bridge - 1pcs
sound pickup - 1pcs
electronic preamp - 1pcs
guitar pegs - 4pcs
metal rod M8x370 - 1pcs
screws:
m4x25 - 9pcs
m4x50 - 1pcs
m4x40 - 2pcs
m3x8 - 4pcs (for pegs)
m2x10 - 4pcs (for electronic preamp)

nuts:
m4 - 12pcs
m3 long nut - 4pcs for hot installation in holes (for pegs screws)

m2x10 - screws for electronic preamp I melt it directly in plastic