This project doesn’t necessarily require 3D printing. Depending what you’re making, it may be sufficient to mount the display breakout boards on something as-is.
These little 3D-printed enclosures are useful for holding domed lenses over the displays. And they’re absolutely essential if creating something wearable. The ambient humidity in a costume will kill exposed circuit boards in no time!
We’ll start with the 3D printing because it affords the opportunity to test-fit these parts before buying the electronics, to check whether they’ll even work in the spot you have planned. They add some bulk behind the eyes and the whole idea may be a bust.
1.5 inch (38mm) cabochons (domes) magnify the screens slightly and give the eyes a cool 3D shape. I found mine at Tap Plastics, but any good plastics supplier should have these…or there’s eBay or Etsy. For good magnification and for the cases to hold them properly, the lenses you use should have a high dome to them…a full half-sphere.
Each enclosure requires four (4) #2-56 flat-head machine screws, 3/8" long, plus matching nuts.
This is another “probably easier to find online” part, unless you’re blessed with a well-stocked local hardware store.
There are separate versions of the enclosure for OLED vs TFT LCD…the mounting holes and cutouts are slightly different. There’s a top and bottom piece for each: for example, “LCD Top.stl” and “LCD Bottom.stl.”
I found it best to print each part as a separate job (rather than tiling all the parts on the printer bed) — less oozing / strings means less post-print cleanup — but every printer is different and maybe yours fares better in this regard.
Some filaments such as ABS are known to shrink slightly (about 2%). You may need to scale the .STL files very slightly larger before printing. DO NOT force parts into a too-small case…THEY WILL BREAK.
File or sand away any major protruberances. If you rinse off the parts afterward, make sure they’re completely dry before assembly, maybe leave them on a fan for a couple hours for good measure.
There’s a lot of variation among cabochons (lenses) from different sources, and even different batches from the same source. So it’s possible they won’t fit perfectly on the first try…
Assembling the screens requires that the electronics be completed first. But since the 3D printing doesn’t apply to everyone, it’s all kept on this page rather than throughout the guide. Therefore, go ahead and work on the electronic assembly starting on the next page, and return here when you’re ready to assemble the enclosures.
I don’t have a 3D-printed case design for the Teensy yet. If this is going inside a costume, you’ll need one, to keep out moisture.
If you’re handy with 3D CAD, it shouldn’t be too hard…a rectangle with some cutouts for wires. Otherwise, you can just get creative with a small plastic box (like some mints or breath strips come in) and hot glue. No rocket science required.
If the lens is loose, it needs to be glued in place. Even if it’s a good fit, gluing is a good idea for added durability! But choose wisely…
Hot glue is too clumsy and random; we need fine control. Other glues are too runny…they’ll seep into the gap and ruin the screen. Some react badly with acrylic and will make the cabochon hazy. (Cyanoacrylate glue is both too runny and causes haze…do not use it for this!)
The enclosures can now be installed into something else (e.g. taxidermy dinosaur head) with your adhesive of preference…hot glue, E6000, etc. and will link up with the Teensy board as described on the “Wiring” page.