What better time of year to get silly than summer? Because when the sun is blazing and the days are getting longer, it’s time to finally let your inner child out again.
So – time for a water fight with a homemade water gun! We’ll show you how it’s done with our step-by-step instructions.
- Preparation: What you need
- Reusable PET bottle
- An air pump
- An empty ballpoint pen refill
- An empty cable tube or aquarium hose 15 cm long
- A bicycle valve
- Hot glue (alternatively silicone)
- Adhesive tape and drill
Tip: Be sure to use a reusable PET bottle with thick walls. This will give your water gun stability and prevent it from breaking the first time you use it.
Simple instructions for building a water pistol
- Before you get started, get the materials above and these step-by-step instructions for building a water gun ready.
- Then drill a hole through the top of the bottle the size of your ballpoint pen refill.
- Clean the refill and cut it to a length of 5 cm.
- Now push the refill through the hole in the bottle cap.
- Seal the gap between the refill and the hole in the bottle cap with hot glue or alternatively with silicone on all sides.
- Drill a hole in the bottom of the bottle the size of the tube you have chosen.
- Push the tube through the hole and seal it with hot glue or silicone.
- Now insert the bicycle valve on the other side of the tube.
- Fix the bicycle valve with tape. Gaffa Tape, Duck Tape or AGT sealing tape are ideal!
- Put the air pump on the bike valve.
- Fix the connection again with tape.
- Secure the air pump to the bottle with tape.
- Unscrew the cap of the bottle.
- Fill the bottle with water.
- Screw the cap back onto the bottle.
- Now pump vigorously with the air pump.
Ready – time to play!
Now you have built your own water gun. Have fun with it! Keep in mind that water jets can be really painful. So make sure your toy doesn’t hit anyone in the face, and above all, never aim for the eyes.
If you want to increase the pressure of your homemade water gun, you can seal the ballpoint pen refill with your fingers at the beginning and only let it go again when some air has already been pumped into the bottle.
Alternative building instruction
Is a “do-it-yourself” water pistol safe?
If you want to build a water gun yourself, of course the safety of your toy plays a role. But don’t worry, a homemade water gun is just as safe as a store-bought water gun.
I want to build a water gun myself that has real power, how do I go about it?
With our step-by-step instructions above, you’ll have a good water gun with enough “oomph”. Of course, you can also find other instructions for building your own water pistol. But make sure that the homemade toy is safe!
How much does a homemade water pistol cost?
The total cost of materials for a water gun in the DIY version is only a few euros.
How long will my DIY water gun last?
Our homemade water gun will definitely last at least one summer. And if you take care of your toy and strictly follow our instructions when assembling it, in the best case you will have fun with your toy even longer than one season.
How big does the PET bottle have to be to build a water pistol?
The size of your chosen PET bottle depends on how much stamina you have for pumping.
I have 30 years of experience and i started this website to see if i could try and share my knowledge to help you.
With a degree a Horticulture BSc (Hons)
I have worked as a horticulture specialist lead gardener, garden landscaper, and of course i am a hobby gardener at home in my own garden.
Please if you have any questions leave them on the article and i will get back to you personally.