CAP Booby-trap

Introduction: CAP Booby-trap

Simple 3D printed booby trap.

Step 1: How It Works

The ball bearings, or 6mm BB's, lock the striker in place.

When the cap is pushed down the BB's fall into the slot and release the striker.

Three bearings are used rather than two in the image.

The system has low friction but will not mis-trigger.

Not shown in the image is the 'reset', as is the system would lock and the cap would not be able to be released again. i.e. single use.

To reset, the striker must forced back down to compress the spring and release the bearings again.

Step 2: 3D Printed Parts.

Here the reset pin is visible, the head of the pin is the CAP holder.

Step 3: STLs

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    3 Discussions


    2 months ago

    Hi, Do you have a sketch or sizes on the spring and pin? Part number?

    Suraj Grewal
    Suraj Grewal

    1 year ago

    just like Hk's roller delay lock.
    I love such designs


    Reply 1 year ago

    Thanks :) i got the idea from air-line connectors, the ones where you push back a sleeve to release it.