I like challenging myself, this is one of my personal challenges I made for myself.
I wanted to design a Nerf gun in one day (1) using only what I have on hand (2)without ordering any “specialty items” (I.e. O-rings), and (3) I could spend $10 at Walmart. This is what I came up with, a nerf gun based around an aluminum miller lite bottle. The piston on the inside uses PETG piston rings to seal against the walls of the bottle, and a one way valve so you can load a dart and the air will be drawn through the one way valve instead of pulling a vacuum behind the dart. Print red parts in PETG and Grey and Blue Parts in PLA
Never designed a nerf gun before, but I’d say that this was a good test on the compression a 3D printed piston apparatus would be able to generate.
BOM: 1/2in dowel 15x M3x20mm button head bolts 15x M3 square nuts 3x M3x40mm button head bolts +3 M3x20mm bolts and +3 M3 square nuts for each barrel extension
Optional: Petroleum Jelly for Piston Lube