Introduction: Electric Pump Water Pistol

About: The RobotGeek team is a 6-man operation that wants to make it even easier to use Arduino to make electronics and robots. Check out our instructables and for all of our awesome kits.

Want to have fun cooling off on a hot summer day with a water gun battle? (I am aware that it's winter at the time of writing this, but it never hurts to plan ahead) This is a simple electronic water pistol. No coding, no microprocessor, just a pump, a battery, and a button. You will need to 3D print some parts for this project, so get your extruder hot and let's get going!

Step 1: Project Parts and Tools List

You will need to 3d print the parts found here.

When printing the nozzle, set your infill to 100%. This will prevent leakage when pressure is on the line.

You will need the following parts to build your water blaster:

Tools you will be using:

  • Soldering Iron
  • 3D Printer
  • 1.5mm Hex Driver
  • 2.5mm Hex Driver
  • Hot Glue Gun

Step 2: Wiring

Solder your cables as shown in the diagram. You will have a ground wire hanging free from the button's cable if you used the cable that comes with the pushbutton. Don't worry about it too much, but if it gives you pause, cover the end with some electrical tape.

Step 3: Assembly

1. Put your button in first using 4 x M3*6 Bolts.

2. Next, attach about a foot of Silicone Tubing to each of the outlets on the pump, and run the outer tube through the hole in the bottom of the pistol grip. It will be harder to put these on later. You'll notice I used a right angle adapter on mine. This isn't necessary, but it did help reduce the kink in the line.

3. Put in your pump with 2 x M2*8 Bolts.

4. Zip tie the battery barrel jack, and slide your battery in.

5. Move around your wires and outlet tube. It's a little tricky fitting everything in, but it's possible. Try not to kink or pinch the tube.

6. Measure the tube and snip off any excess, then attach the tube to the nozzle. Use some hot glue in the recessed area, and zip tie the tube to the nozzle to prevent any leakage.

7. Bolt everything together using 10 x M3*6 Bolts.

Step 4: Go Play!

With everything hooked up, fill the water bottle and thread it into the bottom of your pistol. You're ready for a water fight! We've found this is very effective at keeping cats off the counter, and useful for "motivating" each other to get things done!