Super Soaker Central

Inspired by my school's Robotics team, and is pretty common apparently. Use the LRT as a rubber band to power your gun. I don't quite have a design in mind, but I don't see why it wouldn't work.
Basically, instead of water going in the LRT, pumping puts water in a pressure chamber which then stretches the LRT.
It's probably incredibly breakable, much moreso than regular CPS, but the advantage is that you can (I think) use that really thin wall stuff they sell at Home Depot to get reasonable results.
I guess it also works with rubber bands.
Not expecting this to be a major hit, but it's another way of powering your soaker.

In general the idea should work. It's basically the same as using extension springs.

The issue is the exact geometry. How are you going to shape the pressure chamber? For compression springs (as in say the Water Warriors Pulse series), you can just put a piston in a cylinder and then the spring between the piston and the back end of the cylinder. For extension springs or rubber bands it's not so simple.

Didn't they try this with the Water Warriors Splat Blaster? Or is that just a spring that shoots water?
-Zeda

The issue is the exact geometry. How are you going to shape the pressure chamber? For compression springs (as in say the Water Warriors Pulse series), you can just put a piston in a cylinder and then the spring between the piston and the back end of the cylinder. For extension springs or rubber bands it's not so simple.

I was thinking the inverse of a spring-loaded pressure chamber. It has a piston, pumping water pushes the piston back, but instead of compressing a spring on the other side, the tubing/rubber bands are stretched on the side with the water coming in.
The tubing could be attached all the way around the circumference of the piston, as well as the start of the pressure chamber.

Didn't they try this with the Water Warriors Splat Blaster? Or is that just a spring that shoots water?

The Splat Blaster just uses a spring.

Springs may be better for your purpose than rubber bands. They take up less space and can be combined with plungers to shoot air. Though for robotics, there are few, if any applications where shooting air for a projectile is needed.

For soakers, this probably won't work that well. A plunger is definately needed, but the water gun will need to be in a big crossbow shape for this to work. Even then, it won't work as well as CPS since the force is coming from only one direction.

However, some kinds of surgical tubing should work well for elastic WBL's. I've yet to build any successful ones though, and I never got the cheap 3-man pre-built ones from the stores.

mr. dude wrote:I was thinking the inverse of a spring-loaded pressure chamber. It has a piston, pumping water pushes the piston back, but instead of compressing a spring on the other side, the tubing/rubber bands are stretched on the side with the water coming in.

This works, but it exposes the elastic to the water. Not really a problem for most rubbers, but it will rust springs. However, whatever way you still have the issue of attaching the rubber to both the piston and the front of the cylinder.

It's an idea that will work, no doubt about it. But I'm not sure it offers any advantages. It will be tricky to build and may well end up underpowered.

It's an idea that will work, no doubt about it. But I'm not sure it offers any advantages. It will be tricky to build and may well end up underpowered.

I very much agree with that. I'm only throwing the idea out there as a template for better future ideas.
The advantage I can see is that it can make use of the really narrow, thin wall LRT they sell at Home Depot and Lowe's that would be far too weak for CPS (though I have no idea whether it would be an improvement in this design).