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 so on. Shoot bursts of .177 (4.5mm) steel or lead balls. The power is comparable to airsoft toys. One of the simplest way to convert electricity to a stream of projectiles! Requires additional parts like screws, motor, batteries (detailed list below) and assembly. Shooting slider/trigger can be actuated with a servo. The power is limited by design – it can't be cranked up. With more powerful motor it going to jam violently of break apart. Maximum allowed RPM of the motor is around 10,000. Despite being a toy never point this thing at anyone! Use safety googles: steel BBs tends 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 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 (a few models may be leaked, but no slicing issues so far). There is no special requirements except for 3 main parts: base, stator and rotor. Those should be made of hard plastic (if possible, regular PLA and ABS tends to wear out), 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 a motor's shaft and then press-fit the rotor. Very important: make sure the rotor turns in one plane without any wobble. Make sure it doesn't scratches anything. Use sandpaper to remove any contacts. 4. Sand out sharp corners in channel for BBs. BBs should freely drop in the center of spiral channel and should be able to pass freely to the exit. 5. Glue BB hopper to the feeder base. 6. Install slider and slider's return spring. Make sure slider moves freely. Sand out slider's channel. 7. Assembly the whole thing: it is important to put some washers on M3 screws between base and stator. The distance should be adjusted so the most top of the rotor is ~0.5mm away from stator. The rotor must spin freely inside. 8. Solder all the wiring. Make sure the motor spins in a right direction. ** See photos and video for more details! **