A couple months back my friend requested a pair of hip-packs. They had to be relatively small, hold a mini u-lock, and have a secure pocket for a cellphone. Here's what I came up with:
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8" across the top, ~5.5 deep, 6x2 on the bottom. 1000d Cordura nylon, acrylic-coated poly liner.
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I usually don't use velcro, but since this was a special job I made an exception.
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Typical u-lock holster design. There's some thin padding in the u-lock straps on these, though.
Now, here's how I got to the above bags...prototypes galore:
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This is a nearly complete bag. I pretty much just moved the label and nudged the zipper up a bit. On the final packs, the pocket is lined with a mil-spec oxford nylon.
Below is the first finished design. Zipper pocket, floating liner...super water-resistant but hard to get into. The final design is a little smaller than this but has better accessibility.
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Dumb place to put a label. Whoops.
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Same lock holder strap. I'm also not wild about how the binding looks on this bag. It's an okay design (I use it a lot)...just a li'l goofy on a bag this small.
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For scale.
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No floating liner (above). But no holes in the corners. Hell no.
And here are most of the prototypes I made, excluding some paper ones...and I gave one of the vinyl ones away before I took this. A big thanks to the public library for providing me with such fine prototyping material. Books are great.