Biczooka (bolt action)

thingiverse

I designed this from scratch. I call it the "Biczooka" The design effort was inspired by an aggravating little fly... There are two printed parts. it took me about 2 hours total to print both parts at 0.28 layer height. The printed bolt (with optional bolt extension from the inside of a Bic mechanical pencil) is inserted through the end hole and secured using one M3 screw which goes through the rails and printed bolt hole. The screw secures the bolt into the assembly and acts as a bolt handle that slides back and forth in the slots and serves as mounting point(s) for the elastic bands. A Bic Mechanical Pencil acts as an optional barrel sleeve (outer pencil casing) and bolt extension (pencil lead and eraser holder) It is powered by one or more bracelet loom elastic bands that hook between the slot(s) on the front of the barrel and the bolt screw. The elastics stay under tension even when the bolt is not pulled back so they stay put (until they break). I believe it might be useful for accelerating a variety of things. I built it for fun but it could be dangerous so be careful and wear eye protection if experimenting with it. The elastics break fairly often. Build and use at your own risk. I think it could be improved but wanted to share my effort thus far anyway. I included a .step file for the main part since I think it is an interesting platform to remix. A Bic mechanical pencil is actually tapered inside so put the wider end (closest to where the pocket clip had been glued on) deeper on inside of the barrel if using it as a barrel sleeve. I cut the end off the restriction closest to the pencil tip with a hacksaw and left it sticking out the front of the barrel about an inch. I took the eraser off and slid the eraser holder into the slot on the printed bolt part. You will likely want to cut down the bolt extension to a more desirable length but not too short or it may fall out of the barrel. Slide the bolt into the back and then secure the bolt with an M3 screw (I used one long enough to go through both sides which act as a handle to pull back on before releasing. The M3 screw should cut its own threads the first time it is run through the bolt hole. One future improvement would be to use a round Bic pen tube as a barrel instead because it isn't tapered like the inside of the Bic mechanical pencil. It hits hard and may make sense to use a dowel for the bolt as another possible improvement. Be sure to share your remixes if you play around with it. With a little more effort, I think there is a real potential to dominate irritating flies everywhere. Use at your own risk. Be safe and enjoy.