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A member of my family collects antique porcelain jars, and some of them are missing lids. He mailed me a surviving real handmade lid:


We have 3 options right now for 3D scanning at Hack Manhattan, an XBOX Kinect with ReconstructMe, a line laser scanner (Tony Buser's Spinscan) and Autocad 123D Catch. For this project, I used the latter, which involves taking around 60 images of the object using a (4 MP) digital camera, of which the above image is one. Macro and Flash helped a lot to get a good scan.

The initial 3D object looked like this:


There were some bulges and noise in the model, which I tried to clean up with Meshmixer, but I couldn't get it sufficiently symmetrical. So, I used netfabb-studio to perform two cuts in the X axis, leaving just a sliver of the profile of the lid where it matched the original object best. I then imported this 3D STL sliver into OpenSCAD, and made a 2D projection (DXF vector file) perpendicular to the plane of the sliver, and then used the rotate_extrude command to regenerate the lid model.

A second OpenSCAD script was used to offset and scale the model inside itself to create a wall with real world thickness: Gingerjarstl.png

The final STL was scaled as required and printed in ABS on the PrusaMendelV2 at Hack Manhattan. Acetone can be brushed on top lightly to give a smooth surface, and painted by hand (by an expert!) to the original design.

File:GingerJarLid7 small Gjlabs.jpg