TeensyROM Exposed Case

This is an alternative case for the TeensyROM cartridge for the Commodore 64.  It's designed to be easy to print (no supports), leaving some of the cartridge's larger components “exposed” through cutouts in the case.  Significant inspiration is taken from Stefan Wessels' original case design in the GitHub repo.

Update for TeensyRom revision 0.3:  Use the “TeensyROM 0.3” files for the case shell, along with the LED cover and case button.  This should accommodate an M3 machine screw (12mm recommended) screwed directly into the plastic hole.

Two forms are presented.  One uses an M3x16mm button-head machine screw (as I had handy), and the other uses the tapered screw measurements from the original case.

I printed the LED cover in transparent PETG and glued it into place inside the case top.  This is probably “optional”, and other colors/materials may work.  The size worked well for me on my printer; if you find that it doesn't fit right you can either play with its scaling in the slicer or let me know.

Colored Label

I don't have a multi-material printer, but there are two ways to get colored lettering in this context:

• Carefully “paint” the raised letters after printing.  A metallic Sharpie pen works well for this (with steady hands).
• Create two gcode files.  For the first, use the slicer to add “negative volume” blocks covering everything except the letters.  For the second, add a negative volume block covering only the letters (which are 0.7mm tall), and set a “lift height” (PrusaSlicer printer/extruder setting) or “Z-hop” of at least 0.7mm.  Print the letters file, then change filament and print the other file right over it.

N.B:  I used pretty close measurements, so it's possible that some adjustments may be needed if there are variances between different TeensyROM boards.  (Or that model adjustments or printer tuning are needed for varying tolerance.)

Update Dec. 20 2024

The size and position of the heatsink opening is adjusted slightly for better positioning tolerance.

Added a “developer edition” case top and button.  Recommended to print the dev button in clear filament to also show the Teensy MCU's LED well.

Added a “no screw” case bottom for earlier TeensyROM editions which do not have a screw hole in the PCB.  The “tapered screw” top can be used with this bottom.  (This combination should also be fine for PCBs with a hole, if you don't want the screw hole.)  Note that there is no mechanism to hold this variant of the case together other than friction around the edges.  You may want to use a bit of glue or something.