SD cards have largely supplanted most other card-based storage devices, in all but a few niches. Available in standard, micro, and the rather obscure mini sizes, they’re used in everything from digital cameras to car stereos and console ROM carts. For most users, storing them consists of tossing them in a bag, occasionally in a plastic case that’s barely any bigger than the card itself for a little extra protection. This can get frustrating when carrying multiple cards, but [Dranoweb] has a solution.
[Dranoweb]’s design is similar to a Swiss Army knife, repurposed with many fingers, each with slots for holding everyone’s favourite storage devices. All the parts barring the screw are 3D printed. There are various designs of the storage fingers, allowing the build to be customized to suit varying quantities of SD and microSD cards. There’s even a deep-pocketed piece for USB drives and small adapters, and an oversized design for Nintendo DS carts.
It’s a tidy design that makes it that much less likely you’ll lose your microSD in the bottom of your backpack. Now, if you need to interface with an SD card, we can help you there too.
The first thing to catch one’s eye might be that leftmost seven-segment digit. There is a simple reason it doesn’t match its neighbors: [Juan] had to use what he had available, and that meant a mismatched digit. Fortunately, 3D printing one’s own enclosure meant it could be gracefully worked into the design, instead of getting a Dremel or utility knife involved. The next is a bit less obvious: the display lacked a decimal point in the second digit position, so an LED tucked in underneath does the job. Finally, the knob on the right could reasonably be thought to be a rotary encoder, but it’s actually connected to a small DC motor. By biasing the motor with a small DC voltage applied to one lead and reading the resulting voltage from the other, the knob’s speed and direction can be detected, doing a serviceable job as rotary encoder substitute.
