36 replies to this topic

[Wes7143]

There was some talk a little while back in this thread about using rubber washers for the 2" plunger tube, and the difficulties of it. Here is one solution:

Recently, I have been making one of Rork's SnapBows. It is working good, and now I'm just waiting for the springs from McMaster to arrive. I purchased Every last thing on his list and ended up with quite a few things I didn't need, one of which being a 2" PVC tube. While I was building the snap, my dad fiddled around with it in an attempt to make a Nerf cannon. Here's how he did the plunger head



It's a 1 1/4" cap that he put on the laythe and cut grooves into for the O-rings. It works astonishingly well, and when we were messing around with it, I pushed the back of the plunger rod. The cap we had put in the front had not been drilled yet, and shot off! It made a fairly large crater in the wall. My dad plans on using extention springs, rather compression springs to power his.

Just a different way,

-Wes

[rork]

You people, with your lathes and fancy shoes and hoity-toity ways...

[Wes7143]

You people, with your lathes and fancy shoes and hoity-toity ways...

Don't worry Rork, the SnapBow I made still uses the same rubber washer method as yours. And yes, my shoes are fancy because I lathed the insides to fit my feet perfectly! [/sarcasm]

Actually using the lathe is a good alternative if your local hardware store does not offer rubber washers big enough to make a seal in 2", although I'm not sure where you would go to use a lathe. Perhaps your school's building classroom has a lathe?

[rork]

I'll get around to getting one eventually. Until then, I will wallow in my spite and (On Topic) use O'rings from Mcmaster.

[AssassinNF]

The normal SNAPbow (1 1/4" plunger tube) gets well over 100' with the right dart/barrel combo. I shiver to think what you could do with this monstrosity, which pushes almost twice as much air.

Now think about what a 4" plunger tube would do.

I'm still looking for a spring big enough for my cannon.

[rork]

That would be wildly ineffective. Springers run into a wall of diminishing returns fairly quickly; for example, you can get 70'+ from a Nitefinder, 80-90 from a SNAP-1, and 110 or so from a SNAPbow. Notice how small the gains are in comparison to the increase in spring power/air volume? The Bigbow is interesting--not because it would shoot 200', but because it has enough excess air (which would normally be unused) to compensate for things like inline mags and so forth. Even 2" is a bit excessive; using a plunger tube that massive creates its own set of construction issues. Anything bigger would be truly ridiculous in terms of part cost, machinability, and awkardness. All that being said: I would be impressed if anyone pulled it off, simply from a what-the-hell standpoint. ~Rork

[perezinthenet]

Did you just use the snapbow write up sized up? and what size washers did you use?

[TheNerfLoki]

This is sort of random but what did this

My sock is on differently then usual

have to do with the topic?
On topic: What length barrel are you using?
And lastly:

Did you just use the snapbow write up sized up? and what size washers did you use?

You can tell from the plunger head it is not an normal snap.

Edited by TheNerfLoki, 12 November 2008 - 05:18 PM.

[Quilan Fett]

The normal SNAPbow (1 1/4" plunger tube) gets well over 100' with the right dart/barrel combo. I shiver to think what you could do with this monstrosity, which pushes almost twice as much air.

Now think about what a 4" plunger tube would do.

I'm still looking for a spring big enough for my cannon.

Try a pogo-stick or door-closer spring.

[analogkid]

The door closer spring that I had was about 18" long. It could do the job. That cannon looks awesome, I hope you get it done.

[AssassinNF]

That would be wildly ineffective. Springers run into a wall of diminishing returns fairly quickly; for example, you can get 70'+ from a Nitefinder, 80-90 from a SNAP-1, and 110 or so from a SNAPbow. Notice how small the gains are in comparison to the increase in spring power/air volume? The Bigbow is interesting--not because it would shoot 200', but because it has enough excess air (which would normally be unused) to compensate for things like inline mags and so forth. Even 2" is a bit excessive; using a plunger tube that massive creates its own set of construction issues. Anything bigger would be truly ridiculous in terms of part cost, machinability, and awkardness. All that being said: I would be impressed if anyone pulled it off, simply from a what-the-hell standpoint. ~Rork

Of course it would be inefficient with one dart. That's why I'm going for a minimum of ten per shot.

Machinability hasn't been a problem, parts cost wasn't too bad (I had most of it already), and awkwardness is solved by the fact that its a CTF Defense turret, not a carriable weapon.

I've already pulled it off. I just need to get an adequate spring (or springs), fabricate a trigger (more like a lever at this point), and work out a few problems with my tripod.

The door closer spring that I had was about 18" long. It could do the job. That cannon looks awesome, I hope you get it done.

Thanks, analogkid. It's not a question of if, but when I get it done. I need to get off my ass and get back to work.


And to anyone wondering what the fuck I was thinking in building this - I'm doing it because I can, and because its fun. And for the sheer WTF factor.


Now lets get back to the BigBow. Sorry I momentarily hijacked the thread. My work will get its own thread when it is worthy.

[BustaNinja]

Carbon, Sam and Ryan talked about making a massive SNAP with a big plunger tube like that. Mostly for mortars and stuff. I mean, Carbon already has the ball gun, but he wants something bigger. Thats the awesomeness that is Carbon.