Okay, let me tell you about this little project I cooked up – making my own battery-powered water gun. The store-bought ones just felt kinda weak, you know? I figured, how hard could it be to make something with a bit more oomph.

Getting the Bits Together

First off, I had to figure out what I needed. It wasn't super complicated in my head.

• A small water pump. I found a little 12-volt one online, the kind people use for little fountains or something. Didn't need anything massive.
• A battery pack. I scavenged one from an old RC car, figured it had enough juice. Made sure it matched the pump's voltage, roughly.
• Some tubing. Just clear plastic tubing, flexible stuff.
• A switch. A simple on/off button type thing.
• A water bottle or some container. Something sturdy to hold the water.
• An old broken water gun shell. I had one lying around, perfect for stuffing the guts into. Looked cooler than just a bottle and pump.

That was basically the shopping list. Had most of it lying around in the garage, actually.

Putting it All Together

Alright, this was the fun part, but also where things got fiddly.

I started by taking apart the old water gun shell. Just needed the casing, ripped out the old manual pump mechanism. Then I tried fitting the little electric pump and the battery pack inside. It was a tight squeeze, let me tell you. Had to trim some plastic bits inside the shell with a utility knife.

Next, wiring. This was pretty simple. Connected the pump's red wire to the switch, the other side of the switch to the battery's positive (red) wire. Then connected the pump's black wire directly to the battery's negative (black) wire. I used some electrical tape just to make sure nothing shorted out. Safety first, kinda.

Then came the plumbing. I drilled a hole in the water bottle cap for the intake tube. Ran that tube from inside the bottle to the 'in' side of the pump. Then, ran another tube from the 'out' side of the pump, snaking it through the gun shell to where the original nozzle was. I had to glue the tube in place at the nozzle end to get a decent seal.

Getting the switch mounted where the original trigger was took a bit of messing around, used some hot glue to hold it in place. Not the prettiest job, but it worked.

Finally, I stuffed everything inside the shell – pump, battery, wires – and screwed the casing back together. Attached the water bottle where the old reservoir went. It looked a bit Frankenstein-ish, but hey, it was my Frankenstein.

The Moment of Truth: Testing

Okay, filled the bottle with water. Took it outside. Heart pounding a little, you know? Felt kinda silly being excited about a water gun, but whatever.

Pressed the button...

Whirrrrrr... and PSSSHHHHH! Water shot out! And man, it shot out way better than the original gun ever did. Had a decent stream, went a good distance. Success!

Did have a small leak around where the tube went into the pump initially. Had to tighten the connection there, maybe added a dab more glue. Also, the battery pack got a bit warm after running it constantly, so probably shouldn't hold the button down forever.

Final Thoughts

So yeah, that's how I built my battery-powered water gun. It wasn't rocket science. Took an afternoon, mostly trial and error, especially getting things to fit in the old shell. But the end result? A water gun with some actual power behind it, running off a rechargeable battery. Pretty satisfying little project, honestly. Works great for annoying the dog in the backyard.