Micro Centrifugal Pump

This is a very small pump that can put out a lot of volume for it's size. With a 3D printer you should be able to put this together in about 15 minutes. It is designed for tiny RC boats fire monitors.

3D printed parts

4mm Shicoh motor

drill bit and pin vise as needed

superglue

First step: 3D print parts for the pump. Use a good quality resin to increase the impact resistance of the parts. The housing is very thin. Make sure to check the motor you have at hand and adjust the model if needed. This design is using a Shicoh motor that has a 0.8mm shaft and a 2mm diameter flange. Those motors are available from a variety of sources. Clean up your 3D parts. Remove supports. Use a drill bit and a pin vise to drill out the impeller to the diameter needed for your motor.

Glue the flange side of the pump housing to your motor. A rubberized superglue works well or you can use epoxy glue. Glue the impeller onto the shaft of the motor. Make sure you do not get any glue on the bearing. The impeller bore is going all the way through the part, the safest way to apply the glue is to position the impeller on the motor shaft and then pit a small amount of glue on the open end. It is advisable to run the motor before that to make sure it is running freely without touching the housing. Then glue the suction side of the housing to the flange side, again running the motor before applying the glue to make sure everything fit correctly. you can use 3D printing resin and cure it with some UV light as an alternative to super glue. Seal the end of the Motor with some glue as well, experience shows that those little motors do very well in water without any shaft seal if they are otherwise enclosed.

Time for a final test ! keep in mind that this type of pump is not self priming, it needs to be filled with water before it functions properly.