Working Finger Trap Keychain

This is a cool mini finger trap you can put on your keychain! I made this because this was very cute, and I want to make it as a hanging toy on my bag. My inspiration came from seeing someone make a mini bear trap with metal, but that project was very hard to make because it had lots of tiny metal parts. Therefore, I designed a finger trap that could be almost completely made with only a 3D printer. Now, anyone who wants to make this can do it very easily.

Torsion Spring * 2

• ~0.5mm Wire Diameter
• ~4.5mm Outer Diameter
• ~ 1cm Extended arms
• ~ 6 turns
• Example: https://www.amazon.com/Calvas-Diameter-Torsion-Outside-Jewelry/dp/B07PMH8F2B/ref=sr_1_22?dchild=1&keywords=torsion+springs&qid=1627664749&refinements=p_n_feature_eleven_browse-bin%3A3622111011&rnid=3622110011&s=industrial&sr=1-22

3D Printer * 1

• Any FDM print can do
• Material: PLA
• Example: Ender 3 3D printer

Utility Blade * 1

Plyer * 1

Oil Based Marker Pen

• https://www.amazon.co.uk/Uni-Coloured-Surface-Outdoor-Marking/dp/B00HUPZ0VW/ref=asc_df_B00HUPZ0VW/?tag=googshopuk-21&linkCode=df0&hvadid=534949571216&hvpos=&hvnetw=g&hvrand=4903146608714707755&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006656&hvtargid=pla-1458464604474&psc=1

Ball chian

• https://www.amazon.com/Stainless-Rustproof-Pulling-Extension-Connectors/dp/B07HQR2LWT/ref=sr_1_2_sspa?crid=13HF1I03Q57B2&keywords=ball+chain&qid=1646091511&sprefix=ballchain%2Caps%2C137&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExSktROVFLNlk5M0hIJmVuY3J5cHRlZElkPUEwNzI2NjI1MjFURTJMVzNNQ01ZQyZlbmNyeXB0ZWRBZElkPUEwMzIzMTQzMUlRRzI5UThGT0Y2MSZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

Find 3D models here: https://www.thingiverse.com/thing:4699798

• Download every model except for "all.stl"

Open Cura

1. Load all stl models downloaded
2. Arrange them in a neat and printable way
3. Press "slice", and save G-code file
4. Use 3D printer to print the G-code file

You may need to use sandpaper or a utility blade to cut off excess material or improve surface finish depending on your print. This usually isn't required though.

If you want your finger trap to have color, color each component now before you assemble them.

Watch Video and see how to assemble.

1. Intro: 0:00 - 0:36
2. CAD model process: 0:36 - 4:08
3. Assembly process: 4:08 - 8:58
4. 4. install a ball chain loop through the hole on the side of the finger trap.

Go to step 4 and see the video, 3:08 - 4:00

1. Close the two jaws to the middle
2. Use fingers to push down the spring plates on two sides
3. Open the jaw by bringing them down to two sides again. You should feel the two jaws being pushed upwards by the springs.
4. Pull the middle square block up so that the long thin pin touches and blocks the two jaws from closing.

Press down on the middle of the trap, and it will bite your finger! Don't worry, it won't hurt.

Have fun playing with this toy! You can show it to your friends and hang it on your bag or something.