This is a box to hold 8 1/4" hex drive bits. It is designed to be as small as possible so it can be used with an every day carry size screwdriver.

I spent quite a bit of time trying to find where I could buy something like this. Injection molded plastic would be much stronger than a 3D print, and could be made smaller than what I achieved. But in the end, I had to design and print what I wanted.

I printed this in ABS because I wanted the plastic to not be brittle and have good layer adhesion.

The 1/4" hex drive screwdriver in the picture is sold by O'Reily Auto Parts. It is branded Power Torque with a model number: GM3828 https://www.oreillyauto.com/detail/c/power-torque-tools/tools---equipment/hand-tools/screwdrivers/drive-bits-star-bits/8b81caa6a353/power-torque-9-piece-1-4-inch-drive-phillips-slotted-hex-standard-two-way-bits-set-with-key-chain/ptt0/gm4315 (Edit: I've discovered that an identical driver is sold by Topeak, also sold by RUJOI https://www.amazon.com/Topeak-TT2524-Ratchet-Rocket-Lite/dp/B00P2BB2PE/ref=sr_1_19_mod_primary_new?crid=3LEVKTBR9F6ZL&keywords=RUJOI&qid=1681176980&s=sporting-goods&sbo=RZvfv%2F%2FHxDF%2BO5021pAnSA%3D%3D&sprefix=rujoi%2Csporting%2C140&sr=1-19 ) I'd love to get one of these designed for 4mm hex drive bits.

Instead, I found a 1/4" to 4mm adapter so I could use 4mm bits with the 1/4" driver. I re-designed the holder for 4mm screws. This allows me to carry 13 4mm bits in the carrier rather than the 8 bits that would fit in the 1/4" carrier in approximately the same space.

I would love to have been able to design this as a parameterized project so the number of bits could be easily changed, but FreeCad does not allow the number of elements in a rectangular array to be specified by an equation or reference a spreadsheet.

Edit: I managed to drop this on a hard floor. It dumped & scattered the bits, and broke the latch. I have re-implemented the design in OpenSCAD since that allows me to make the bit size and number of bits parameters. I also changed the latch design to something I hope is more robust, and wont break when dropped. The .scad file is configured for 13 4mm bits, but can easily be reconfigured for 1/4" bits by commenting out the 4mm bit parameters and uncommenting the 1/4" bit parameters. It can be configured for other sizes by editing the parameters.

Edit 2024-07-03: I have performed an accidental drop test on the newer design. This time no pieces broke off, but it did crack, and scatter the bits on the floor. Not sure how to make it stronger without making it bulkier.