This BB Shooter Has a Spring, But Not For What You Think
1 min read
Summary
A 3D printed blaster that fires 6mm BBs has been designed using a four-bar linkage, meaning it requires no additional hardware and prints in a single piece.
The spring only acts as a trigger return rather than assisting with firing, offering a clever mechanism for launching projectiles.
Instead of the usual way of firing via a trigger that pulls back a striker and puts it under tension using a spring, the four-bar linkage transforms a rearward pull into a forward push of the striker.
This then pushes the BB, with its forward motion arrested by a detente, meaning once tension passes a threshold the BB pops past the detente and flies.
The mechanical advantage of the linkage means the trigger doesn’t need to do much work, with the spring simply resetting the trigger after firing.
