Sabot-Pressurized Water Balloon Launcher (no bike pump!)

[DX]

This idea came to me when I was digging in the depths of CPS Central in search of my Douchenator. Finally found the thing and took it out to see if it still works. Noticed it still had an outdated Pringles can sabot and was playing with it when I realized that it moves a TON of air when it slides down to the bottom of the barrel. With some duct tape layers, it was moving about 8" of 3" diameter air back through the open ball valve, far outstripping the volume moved by a bike pump. So I thought, what if this could be utilized as the pump, bypassing the need to tap a schrader with a bike pump.



The design won't be the king of efficiency, but it's the only way I can think of that would allow air to be pumped in and air to fire out the same opening. When the sabot is done pumping and the second valve is opened, everything behind the primary valve becomes the PC, so I'll have to glue this thing religiously. With that in mind, it is possible that the PC could be shaped differently to make the gun more compact.

There is some uncertainty as to the worthwhileness of the design. In theory it would pressurize faster than a bike pump because the sabot moves much more air per stroke. However, you can really slam it in with a floor pump, so what happens when the pressure gets high, would it be too difficult to shove the sabot down? Pringles cans are not known for durability, especially since you have to cut off the rim for it to slide better. You also have to pump this hard and fast to force the check valve to open, the only ones I have for PVC are meant for water. A prelim test verified that the valve will indeed open, but you do need to shove that sabot fast.

The main plus is that it saves you the need to spend $40 on a good floor pump or $60 if you want a pump that will actually last more than one season. If you have multiple WBLs, but not multiple pumps, it could be a viable option if it ends up generating enough pressure. I am anticipating not being able to put in as much as a bike pump, so this would be a shorter range gun in the 200-300ft range (G2 Douchenator maxes out around 800ft).

[atvan]

How are you gonna pull the sobot out when you want another pump? Interesting idea. Similar to my idea for nerf in which the shells have compressed air and operate similar to a airsoft grenade launcher grenade.

[isoaker]

Apart from atvan's sabot-removal question that might be solved by attaching a pole/wooden dowel to it, the biggest problem is from the fact that the sabot moves so much air per push. Trying to move large volumes to pressurize a chamber ends up being much more difficult than moving small volumes at a time (you're basically going backwards from large to small so you're losing out on the force multiplication advantage you get when pushing on small areas).

Definitely build-able, but I don't think one will be able to pressurize it as well as WBLs pumped up using a bike pump or other smaller-volume-type pump.

[wetmonkey442]

How are you gonna pull the sobot out when you want another pump?

You shoot it.

[isoaker]

How are you gonna pull the sobot out when you want another pump?

You shoot it.

HAH! I audibly laughed at this comment!

[HBWW]

Originally, this is how I thought the Douchenator worked at first before reading through the article more thoroughly. Good old days...

Pringles cans often don't seal anywhere near enough to be useful for this, but putting that aside, even if we had an ideal sabot (say, a sturdy piece of foam such as a short segment of pool noodle that fits in properly, or a sturdy cup/conically shaped piece [made of plastic and/or rubber perhaps] perfectly cut and made to seal), there is only so much that can be done. Essentially, the concept is akin to a spring powered WBL; being able to power it up in one go. It also carries the same problem; way too little power, and iSoaker just mentioned that pressures could build up to the point where it can't be pushed anymore. (Though this obviously depends on PC chamber volume, barrel diameter/length, etc.)

A better application of this is using it to assist bike pumping but even then, it doesn't seem like it would add all that much air, and breech loading is probably faster and more efficient anyway.