
TrussFab: Fabricating Sturdy Large-Scale Structures on Desktop 3D Printers - pretsel
https://hpi.de/en/baudisch/projects/trussfab.html
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emj
How do they join the bottoms of the bottles? They seem to be prejoined in the
dome timelapse.

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unwind
Good question! Had to look it up in the paper, and it turns out they use wood
screws.

Either regular ones using a long screwdriver through one of the bottle's
mouths, or more specialized double-ended screws (with two points) that let you
grab the bottles and counter-rotate them to drive in the screw in both
bottoms.

Neat, I hadn't thought the bottoms of PET bottles had enough material to make
this work, I would have expected bolts with nuts, i.e. more metal-to-metal in
the fasteners.

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mrfusion
These would be cool to sell on etsy.

I'm guessing you could get the connectors mass produced pretty easily?

Is there anywhere to get empty botttles in bulk?

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akeck
I have an idea that I haven't tried yet. 3D print hollow joints that, for
example, connect wood panels into a book case. Then fill the hollow spaces in
the 3D printed joints with concrete.

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blacksmith_tb
That has potential, though it may be hard to find a shape that's open enough
to get concrete packed into, while still wrapping around the panels
effectively (and you'd want to use a concrete with fibers mixed in to help
with shear[1]). It might be possible to use epoxy resin instead.

1: [https://en.wikipedia.org/wiki/Fiber-
reinforced_concrete](https://en.wikipedia.org/wiki/Fiber-reinforced_concrete)

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markvdb
I would love to make a few of these connectors on my laser cutter. Seems like
I will have to look carefully for source files...

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macawfish
This is incredible. Make sure to watch the video to get a sense of just how
rigid these things are!

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matthewhall
That is sweet

