Working Pennyshot Derringer Toy

Scrooge's Shotgun, The Door Knocker, Lincoln's Revenge - the Pennyshot Derringer!

A 'working' derringer toy from the videogame Hunt Showdown - a clever, homemade-looking last resort. This does not fire anything - just a fun fidget. The hammer can be cocked, and slams forward when the trigger is pulled. The barrels can be hinged forward, and the shells removed. The penny 'rounds' can be slid out, to simulate firing the shells - which should be useful for photography / filming.

All parts are designed to print flat with minimal supports. You will need 5x 20mm m3 screws, and 1x 10mm m3 screw. You will use snips of filament to hold some parts rigid. You will use rubber bands as the trigger/hammer 'springs'. Optionally, you can fill the grip with old pennies to add weight (how fitting).

20mm m3 screws:

• One as the front pivot of the barrels
• One as the top pivot for the latch
• One as the pivot for the hammer
• One as the pivot for the trigger
• One as the holding the right grip to the frame

10mm m3 screw:

• One as holding the left grip to the frame (will 'meet in the middle' with the right-grip screw)

Snips of filament:

• Hold the firing pin in the hammer
• 2 locators on frame/grip to prevent rotation

Rubber bands:

• One to pull the hammer to the 3 frame anchor posts
• One to pull the trigger to the 3 frame anchor posts The exact rubber band thickness/elasticity is not critical, and there 3 posts so you can fine-tune exactly how much force you want. If you aren't getting enough force, simply double up on the bands. The posts have small notches in them to better hold the bands in place.

To create shells, you can print the 'shell-long' to get a standard shotgun shell, or the 'shell-short' and 'penny post inserts'. This will allow you to paint the inserts like pennies, glue them together, and slide them into the 'shell-short'.

In a 'real' derringer of this kind, the hammer would have an internal clockwork mechanism so that the firing pin toggles up/down after each shot. There would be an internal cam, pushrods, etc. This was too fiddly for me to design (and you would hardly notice from the exterior) - but feel free to remix if you are up for the challenge! You can get my onshape cad here - (note that this is still somewhat a wip)

WARNING: don't flaunt lethal-looking objects in public. It is dangerous and unethical to scare others in this way.

Category: Mechanical Toys