Nerf Mega-Blaster

[Brad]

I'm making some sort of spring-powered Nerf ball blasting device. My goal is to make it as compact as possible while still able to shoot regular nerf ballistic balls. That's why I chose to make is spring powered rather than air powered as actual Nerf ball blasters are. I started with a Nerf Reactor . I took it all apart. I plan on reusing some of the parts including the tube and the cap that fits inside the tube. The original gun is very simple air-powered toy so the end result isn't really going to be anything like it.


I have assembled a few of the pieces necessary so far. Here is an image showing all the pieces and their dimensions.


Here is an image of the basic idea of how I plan on constructing the blaster. Inside the yellow cap there is a washer, I plan to weld the spring and a nut to this washer. The metal rod is threaded and will attach to the nut. The washer itself will probably just be glued to the yellow cap. There will be a backplate on the end of the tube with a hole in the center for the rod to slide through. The spring will press against the washer and the backplate and compress when the rod is pulled backwards. I need to devise some of catching the rod when it is pulled backwards and then releasing it when I want to shoot (I'm calling these mechanism the cocking mechanism and the triggering mechanism respectively.) I'll also need something to prevent the rod itself from shooting out the end of the tube like a spear gun.


Nothing is actually constructed yet, I'm still in the process of designing the blaster and collecting parts. My main design concern at the moment is the best material for a backplate and the best method for attaching it to the tube. Let me know what you guys think.

[zourtney]

Woah. Mad CAD ski'lz, maaaaan.

That looks pretty cool. For a catch, you could add a large washer to the middle of the rod. The washer would only have to be a little bigger than the barrel and you could keep it in place with one nut on each side. If that doesn't make sense, post the model and I'll edit it and post a picture.

[Nick]

Make sure whatever catching the rod is metal and has padding behind it or the plastic tube might crack.
But awesome! It it works well we should all make one. We can go as space troopers with ball-blasters!

You make that is autocad? It is indeed impressive.

[Brad]

I used that Sketchup program to do the modeling. It's really easy to use.

I'm thinking that the back plate piece is going to be plastic reinforced with a metal washer (the spring pushes against the metal washer). I've still got to find a good method of attaching the back plate to the plastic tube. I don't want to drill into the plastic tube because I think that'll actually weaken it rather than make it stronger. But that connection is going to have a ton of force applied to it by the spring so it's gotta be strong....

I'm with you on the catching mechanism, some kind of washer with padding applied to it and to the back of the back plate should be good enough to stop the rod from shooting out the front of barrel.

I still need to find some method of holding the rod back and then releasing it (besides physically holding the rod back with my hand). Basically I need a mechanism to keep the blaster cocked and another to trigger it. Those mechanisms depend greately on what I'm gonna put this thing into though. I don't plan on leaving it just a barrel with a rod sticking out of it.

I'll probably work on some ideas for a back plate and upload a couple more model pictures sometime today.

[Brad]

Here are a couple more images of my current design. You'll have to check out the image pages for more detail as I'm too lazy to rewrite any of it here.

[Nick]

Nice. I guess I will have to play with the sketcher a little more. I never found out how to make objects to a specific size and that frustrated me.

[zourtney]

Yeah, I would recommend it. It kicks Rhino's butt for easy-of-use. It lacks a few really simple concepts (most notably mirroring!) but you can do anything you want to, I'm pretty sure.

[Brad]

I've got all my pieces now. I just need some welding. Too bad I don't know anybody with a welder....

[Nick]

I weld. I will weld the crap out of that thing! Just let me at it!

[Brad]

Cool! We'll have to figure some time to get together to weld stuff.