The kinetic brick - rapid fire toy BB gun

thingiverse

The Kinetic Brick - Rapid Fire Toy BB Gun Meant to be mounted on RC sentries, tanks, and other vehicles. It shoots bursts of .177 (4.5mm) steel or lead balls at a rate comparable to airsoft toys. One of the simplest ways to convert electricity into a stream of projectiles. Requires additional parts like screws, motors, batteries (see detailed list below), and assembly. The shooting slider/trigger can be actuated with a servo. The power is limited by design - it cannot be cranked up. Using a more powerful motor will cause it to jam violently or break apart. The maximum allowed RPM of the motor is around 10,000. Never point this toy at anyone! Use safety goggles: steel BBs tend to ricochet all over the place. Additional Parts List - RS-380SH brushed motor. - Two 18650 li-ion cells to power the motor or any other DC power supply of 6-8V and current up to 5A. - Some wires and a switch. - 2X M2 screws to mount the motor. - 4x M3x40mm screws. - 4x M3 nuts. - Some M3 washers. - 2X short M3 screws and one tension spring (optional, not required if actuated by servo). Assembly 1. Print all the parts (some models may be leaked, but no slicing issues so far). There are no special requirements except for three main parts: base, stator, and rotor. Those should be made of hard plastic (if possible, regular PLA and ABS tend to wear out), and the rotor should be printed with 10 perimeters and 15-20% infill. No support. 2. Screw the motor to the base. 3. Add a couple of washers on the motor's shaft and then press-fit the rotor. It is very important that the rotor turns in one plane without any wobble. Make sure it doesn't scratch anything. Use sandpaper to remove any contacts. 4. Sand out sharp corners in the channel for BBs. The BBs should freely drop into the center of the spiral channel and be able to pass freely to the exit. 5. Glue the BB hopper to the feeder base. 6. Install the slider and its return spring. Make sure the slider moves freely. Sand out the slider's channel. 7. Assemble the whole thing: it is essential to put some washers on M3 screws between the base and stator. The distance should be adjusted so that the top of the rotor is ~0.5mm away from the stator. The rotor must spin freely inside. 8. Solder all the wiring. Make sure the motor spins in the right direction. **See photos and video for more details!**