Intro: How to Make a Mini Water Pump
This tutorial is on how to build a mini electric pump (for pumping water). The pump can be useful for small applications or just as a fun craft. One of the best things about this build is that almost everyone should have access to the materials needed as none of them are special parts. Before we start off I would also like to mention I used a very small and weak motor so if you wanted your pump to have more pressure you would only need to use a larger motor. If you plan to build this I recommend you watch the full video here. For more projects like this you can also check out my YouTube channel or my website joshbuilds.com
The materials you will need for this builds are:
- A small motor. (Can buy online, at hobby store, or take from dollar store toys)
- A plastic candle holder (can also use a Gatorade bottle cap)
- Thin hard plastic (plastic food containers)
- Lots of hot glue
Step 1: Making the Impeller
To start of the build we will start by obtaining the pump housing. For this we will need the plastic candle holder (or 2 Gatorade lids can be used). Next we need to make the impeller. The bottom of the impeller will be made out of a plastic sheet. The piece of plastic I used was food packaging. I use a compass to trace a circle slightly smaller than the pump housing onto a piece of plastic. The cut out the piece of plastic and color it red to it can be seen better. Once I cut it out, I also drill a hole in the center so it can be mounted onto the motor at a later time
Step 2: Making the Impeller Blades
Next we need to make the blades of the impeller. To do this I cut out a long thin piece of plastic and cut it into 4 smaller pieces. I glue these four smaller pieces onto the disk I just made. The four smaller pieces can then be glued onto the disk.
Step 3: Attaching the Motor
Next I drill I hole into the bottom of the pump housing. The shaft of the motor will need to fit through that hole, so it should be drilled larger than the diameter of the motor shaft. Next I will put glue around the face of the motor and attach it to the bottom of the pump housing (candle holder). Make sure to seal the holes on the face of the motor so water doesn’t get through.
Step 4: Attaching the Impeller
After this we will now need to put glue in between all 4 blades and attach it onto the motor’s shaft. Once the glue dries you should rotate the finished impeller to make sure it does not chafe against the sides or bottom.
Step 5: Closing Off the Pump Housing
Next we will need to seal off the pump’s housing. For this I trace out the housing on the sheet of plastic and cut out the plastic circle. Before attaching the plastic circle you should first drill a hole the size of a straw in the plastic circle. Also drill a hole the size of a straw in the size of the pump housing. This will serve as an entrance and exit for the water. Next I glue a straw onto the entrance and exit. It is important that glue is put all the way around so it will stay water tight. To finish it off, I glue the circular piece of plastic onto the front of the pump’s housing. The blades of the impeller should be at a height where they will not touch the circle that is attached to the front. If the impellers have too much height, they should be trimmer until they fit. The front of the housing should be glued on so that if the straws are sealed, the pump housing will be airtight. Once this is done you can test the pump.
Step 6: First Test
When testing the pump make sure to suck water through because it must be filled with water to work. As you can see the pump works decently (see video). A larger motor or laying the pump down horizontal instead of vertical would increase the performance. In the next step i show a different modification i made to make the pump work a bit better.
Step 7: Modifications
I found that the design done first worked, but could possibly be improved. Instead of forcing the water to leave perpendicular to the housing, I decided to try letting it leave tangential to the housing which should be a more natural way. TO do this I simply elongated the hole on the side and cut out part of the bottom of a straw. Once that was done I glued it on with lots of glue and it was ready to test again
Step 8: Final Test
The final test seemed to work a bit better but I found a larger motor would most likely give better results. I also realized I was comparing my project to pumps that had the water source at the same level as the pump whereas mine had to draw the water up a few feet which means mine had to do more work. I figure if I turned my pump horizontal instead of vertical it may have shot water out with more pressure.