Film Capsule

When I was growing up, my dad always kept old 35mm film canisters around the house as convenient storage for small quantities of nuts and bolts, nails, and the like. I realized that since few people use film anymore, that the film capsule is slowly going extinct.

So, in the interest of maintaining a well-organized, versatile toolkit, I made my own. As best as possible, all dimensions are true to the original standard-issue grey-top black-bottom 35mm film canister.

Print Settings

Printer Brand:

RepRap

Printer:

Folgertech 2020 Prusia i3

Rafts:

No

Supports:

No

Resolution:

.2mm

Infill:

40%

Notes:

The body can be any rigid material; the cap, however, needs to be printed out of a flexible material. I used Alchement black flexible TPU from Amazon, but most Ninjaflex-like filaments will probably work. Flexible filament was used in the design because that was the way the old-style 35mm film capsules were made. Let me know in the comments how other materials work.

Use in Backyard Rocketry

The other childhood memory of these film capsules was making Alka-Seltzer-powered "pop rockets" I haven't tested how well these will hold pressure yet, but presumably they will work nearly as well as the real thing. For those who aren't familiar, the procedure is as follows:

1. Collect some paper, water, and Alka-seltzer tablets.
2. Roll paper around the film capsule to make the body of the rocket. The capsule should have the cap pointing down at the bottom of the tube, and the cap should be easily removable. This capsule is your rocket engine.
3. Fashion a paper nose cone to put on the other end
4. Go outside, somewhere you don't mind making a mess.
5. Hold the rocket upside-down, and pour in enough water to fill about the bottom quarter of the capsule. You can experiment with the amount of water used, as it will change how the rocket flies.
6. Drop in the Alka-Seltzer, and quickly cap the capsule. Quickly set the rocket down, back away, and prepare for launch!

Note: I take no responsibility for any messes or explosions that may result. Use with care. Adult supervision recommended.