SD2IEC enclosure

This project is for a fully-printable enclosure for the cassette-port-powered Bitsretro version of the well-known SD2IEC project (link below).

Modern electronics just keep getting ever smaller, with some stuff already being too small to handle easily,  and as we retro geeks age, it just keeps getting worse (at least for some of us).  Such is the case with microSD cards.  Those things are just too damned small and yet everyone insists on using them!  This accessibility problem is further exacerbated by this strange trend of designing devices to just plug directly into the back of the machine when they otherwise ought to be separate peripherals.  In the case of SD2IEC, this design motif puts the card out of view and pointing away from the user.

This project seeks to restore that lost accessibility with the help of some wiring and the addition of a microSD-to-big-SD extender cable (link below), and do so in a way that's actually retro-looking, in this case to look like a classic Alps-mechanism 1541 disk drive.

Obviously you will need to remove your SD2IEC from its original case, and ditto for the big-SD end of the extension cable.

Some soldering is required.

In the pictures, I sacrificed an old serial cable that had end connectors I could open up; I cut off one end and wired it to a JST 2.54mm 6-pin connector, matching the pinout of the cable that originally came with the device.  Since a serial cable has 6 wires and we need one more to provide power, I repurposed the wire that was being used for ground, and then used the cable's shield itself as the ground instead, since they're just connected together inside the C64.  The repurposed wire extends back out of the connector housing, ending with a classic cassette port power tap salvaged from an old printer interface.  At the SD2IEC end, this wire goes through a single-pin connector to the 5v input at the SD2IEC's original cassette port connector.

There are holes provided on front to extend the device's activity and error indicators -- I simply soldered wires directly to the SD2IEC's original LED's, leaving them intact.  The enclosure's holes are sized for regular 3mm round LED's.

There are three pairs of cuts on the sides that create flaps you can press in on to actuate the SD2IEC's buttons.

The badge is a bit of a curiosity.  I chose to make mine with a gray base section, and switched to silver at 1.1 mm up, and have provided a .3mf to facilitate that.  I then colored the rainbow stripes with Sharpie markers.  I've also provided the various bits of the badge as separate model files to allow you to construct a fully-color-printable version, but how you'll go about doing that is entirely up to you -- I don't have multi-extrusion, let alone an MMU or Palette, so I have no way to test that method.

The strain relief is sized for a ~5mm cable, but you might be able to cram up to 5.5 mm thick cabling into it.  Then either glue it to the cable on the interior end, or do what I did and secure the strain relief to the cable with a really tight zip tie.

Most of the parts just snap together, no fasteners needed, though you'll need blobs of glue to secure the LED's, some double-stick tape to affix the badge (and possibly glue if you're printing it in parts), and the aforementioned zip tie.

I chose not to expose the USB port or the 4-pin header, as I don't need either of those for my use case (I'm not even sure what they're for).

Important:

• The big-SD end of the extension cable is fragile - bend it too many times and the ribbon will break off.  If you're extremely careful, you'll be fine, but I'm clumsy and a bit heavy-handed, so I chose to desolder the ribbon cable on mine and flip it over so that it leaves the board in the direction of the SD card slot.  Then I bent it back the other way and secured it to the bottom of the big-SD mini-board with a piece of solid wire (still with its insulation on, mind you) to act as a strain relief.

• You will notice that the big-SD end of the extension cable is flipped-over compared to the microSD end, adding a half twist to the cable.  When you put the case together, be sure the cable lays mostly flat, lest it dig into something pointy and break or short-out.

• Make sure any wire joints are well-insulated!  It would be a good idea to add tape or heat shrink tubing around the single-pin power connection, lest is come loose and short-out on something.

Filaments used:

Atomic khaki PETG Pro for the main body of the enclosure, Atomic black PETG Pro for the faceplate, Atomic gray and metallic silver PETG Pro for the base and text/etc parts of the badge, and Sain Smart black 95A TPU for the feet and cable strain relief.

Print settings:

Nothing too special here - 0.4 mm line width, 0.2 mm layer height for most parts, 0.1 mm layer height or thereabouts for the badge. The dual-color badge .3mf uses the Arachne perimeter generator (I normally use classic mode), and does create less-than-0.4 mm lines, but the result still prints just fine with a nozzle of that size.

Credits:

This model is entirely my own work, except for two things: the "commodore" text and logo (both on the badge and on the enclosure top half) came from https://www.printables.com/model/1222617-commodore-computer-logo/related .

Related product links:

Bitsretro SD2IEC:  https://www.amazon.com/dp/B0D7GT4W73 

microSD-to-big-SD extender cable:  https://www.amazon.com/dp/B08SW7ZCDM