M84 Training Grenade (Impact Resistant)

M67 Fragmentation Grenade Trainer: https://www.thingiverse.com/thing:5665277

This is a M84 stun grenade made for my ROTC unit for tactical training. It's designed to accept a 4.25" section of 5/8" threaded rod through the center of it to keep it rigid and add a convincing amount of weight to it for throwing. Use it for your own tactical training, airsofting, and more!

Some assembly tips found via trial and error:

- Print the body of the grenade vertically
- Print the fuse of the grenade vertically but inverted (top flat face on print bed)
- Print both separately, TPU strings readily
- Cutting the threaded rod will result in burrs that complicate inserting it, bevel the edges for easier insertion
- Heating the rods in the oven to about 300F lets you temperature fit the rods for easier fitment and stronger adhesion
- Inserting the rod into the grenade body first lets you screw on the fuse very easily