DIY Electric Sprayer Tank

my mom was unable to use backpack type sprayer tank due to back pain.So i decided to build one trolley type. Take a look on the tank in action in videos above. The sprayer tank has very long sprayer hose.

Step 1: Materials Needed

Things need to prepare:

1. Small luggage trolley, I bought it at local hardware shop Mr DIY.

2. Car wash pump, bought it from China using shopee app. It is a self priming diaphragm pump.This pump draw around 3 Amp when running on 12V battery although it is labelled as 60W. There is a screw to adjust the pressure of the pump, see the second picture's label. you will need to adjust this screw if the pump vibrate too much when pumping while you press the trigger at the spray wand, try increase the pressure a little bit. The pump will stop pumping automatically when the pressure reach the target pressure.

3. spray wand, bought it from china using shopee app too. it has adjustable nozzle to set the spray pattern. For my application of spraying grass, I set to fine mist.

4. Paint/oil bucket or. Prefer to use paint bucket because it is easier to clean. The green bucket shown in picture is Petronas gear oil container.

5. Some self taping screws for mounting the pump.

6. a piece of wood.

7. 12V Rechargeable battery with good capacity that sustain over the period that you need for the operation. The battery in the photo is lithium battery with internal protection from over discharge.

8. some metal wire.

9. Two L brackets.

10. Drill or anything that can make holes on the wood.

Step 2: Assemble the Tank

1. Remove the cigarettes plug from the pump's wire. Or directly cut off the wire from the plug. we will connect this wire to our battery.

2. place the bucket to the luggage trolley and fix it by tying with the cable.

3. place the wood above the bucket and tie it to the trolley by using metal wire. Before you can tie it, you will need to make some holes on the wood/ board using drill or nail.

4. attach the pump to the wood by using the self tapping screws.

5. put the pump inlet tube into the bucket. The inlet tube come with filter to prevent coarse particles clogging the sprayer nozzle. (However the filter is very light and it likes to float on water.try tie a stone or anything heavy to make it sink into water or liquid.)

5. attach the L bracket on the other side of the wood to hold battery.

6. Place the battery onto the L bracket and tie it using metal wire or cable tie to the wood.

7. Make sure the switch of pump is off. You can connect the battery wires to the pump's wire, no polarity. wrap the connection with wire tape to prevent short circuit.

8. the setup is ready. you can test it by filling the bucket with water and turn on switch of the pump. The pump will start pumping, soon you will realize it continues pumping non stop, but water does not flow into the hose. Press the trigger so that the air in the hose can be pumped out through the nozzle. Pressure cannot build up and pump won't stop pumping if the air is trapped in the hose.

Step 3: Test the Sprayer

I tied a bent conduit to organize the long hose that come with the pump.