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Proto Board Holder: Revised Screw Mounts

Improving the crystal tester’s (nonexistent) grounding requires a band of copper tape around the inside of the proto board holder. Rather than cut the tape lengthwise to fit the holder, a new one will be just tall enough:

Proto Board - 80x120 - revised inserts - Slic3r

Proto Board – 80×120 – revised inserts – Slic3r

While I was at it, I deleted the washer recesses, because those didn’t work out well, and fiddled the screw holes to put the inserts in from the bottom:

Proto Board - 80x120 - revised inserts - detail - Slic3r

Proto Board – 80×120 – revised inserts – detail – Slic3r

Although the overhang inside the holes will be ugly, I’ll epoxy the inserts flush with the bottom and nobody will ever know.

The copper tape now makes a tidy ground strap:

Crystal Tester - ground strap - rear

Crystal Tester – ground strap – rear

With a gap in the front to eliminate the obvious loop:

Crystal Tester - ground strap - front gap

Crystal Tester – ground strap – front gap

The OpenSCAD source code as a GitHub Gist:

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  1. #1 by solaandjin on 2017-06-13 - 14:33

    I know you don’t care about looks, especially on an internal feature, but I did successfully incorporate one of nophead’s ideas for printing holes in midair (http://hydraraptor.blogspot.com/2014/03/buried-nuts-and-hanging-holes.html) in a design once. It requires three layers; the summary of the idea is you build up an using only bridges. Rectangular gap in the first layer, to a square in the second layer bridging transversely, to the final octagon in the final layer by cutting off the corners. You can do something similar for a hexagon, just bridging pairs of opposite sides at a time.

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