Backpack modification
Written by Ben
Last updated on 2008-01-21
Backpack modifications are one of the most popular modifications. Putting water in a backpack allows you to carry more water than your would on your arms. They're not for everyone obviously, but if you want more water, you'll get that with a backpack.
Backpacks aren't for every water gun either. On recent Max-Infusion and Aqua Shock Super Soakers, you can buy a small backpack to use with them. If you want more water capacity than those backpacks provide, I would still suggest buying the backpack to get the pieces to attach the backpack to your Super Soaker. Pressurized reservoir water guns also can not use a backpack unless the backpack is pressurized too, but most people don't consider adding backpacks to those water guns because they are weaker.
I suggest using frame backpacks because they distribute the weight on your hips rather than your back. Camping and hiking are hobbies of mine, so I have a lot of frame backpacks, but you can build one if you don't want to buy a new one (do a Google search for a lot more information on that topic). I also suggest wearing backpacks correctly because if you don't, you'll really hurt your back.
The many options
You can build a backpack from many many things. Inflatable water containers like Solar Showers and water bags are common. Rigid options like PVC drain pipe, ABS pipe, solid water containers like the 2.5 gallon containers, and large containers for things such as cat litter are common as well. Camelback style water containers designed for backpacks are possibilities too. All you have to do is store the water in something, put it on some sort of backpack, and attach that to your water gun.
I am using a Solar Shower to construct this backpack. Solar Showers carry a lot of water (more than you will use, so do not fill them completely), are durable, and are cheap. The Solar Shower I bought cost less than $5.
Materials
The materials required are Solar Shower, a tubing coupler, a backpack, 4 tubing clamps, and some tubing. Variations of this design can be made, so you're not fixed into any specific sizes of each part. Solar Showers are sold at camping stores and in the outdoor section of many stores such as WalMart.
Building the backpack
Above are all the parts I have except for the tubing and tubing clamps.
The image above is the Solar Shower out of the box.
I cut the tube leading to the shower head off because I do not need the shower head.
Next I constructed a coupler from two tubing barbs and teflon tape. The coupler was then attached to each end of the tube and tubing clamps were added on.
The backpack and a homemade water gun I used with it are above. The Solar Shower now can be attached to a frame backpack or put into a normal backpack.
Attaching
You have two many possibilities for attaching the backpack: attaching to the included water reservoir or removing the reservoir and attaching directly there. On homemade water guns you usually attach directly to the water gun with a tubing barb and a tubing clamp.
To attach to a built in reservoir, you can drill a hole in the top of the reservoir and epoxy a tube in that hole. Some people removed the caps and used a rubber stopper with a hole in it (for the tube) as a new cap. There's a lot of possibilities obviously.
To remove the reservoir and attach where the reservoir used to attach on a non-homemade water gun, you have to essentially epoxy the tube onto the old reservoir input. You also can devise a system with O-rings that is less permanent, but few opt for attaching directly to the internals.