Centrifugal Water Pump

Hot off the smoking Anet A8! 🙂

After being given a broken Anet A8, complete with melted wires, I set about fixing it and upgrading it with Marlin Firmware, level sensor and flexible steel print bed.

This is my water pump design; with the main aim being to teach myself 3D design and 3D printing. Also figured that I might as well make something useful; as I needed a small water pump to remove water that collects under the house. Also a good test of PLA in quite harsh conditions; the dirty pump in the picture has been in use for nearly a year.There’s no pump curve or other engineering design behind it; it’s just made to fit the small space and the size of the hose I had.

There’s a Version 2 & Version 3; Version 1 didn’t work so I haven’t bothered to upload it. Version 3 has a bigger outlet and a thicker lid. Also tidied up the way it was drawn around screw holes etc.

I recommend that for both that you use the short impeller; it actually moves more water. The tall impeller pushes too much water with the motor I’m using and just back pressures the pump housing.

In this application the pump sits on long screws and is always underwater. The motor sits above water and is triggered by a float switch from a boat store. I also use a DC speed controller with soft start; connected to an old 12VDC battery, as the current draw from the motor is up to 18 Amps.

(ps: Can’t figure out the Thumbnails bit, so not all images are present)

• DC Motor is a “770” style motor from a local electronics store.
  https://www.jaycar.com.au/standard-high-power-d-c-motors-11800-rpm/p/YM2770
• Soft starter / DC motor speed controller
  https://www.ebay.com.au/itm/Speed-DC-Motor-Controller-Governor-Module-Digital-DC-brushed-21KHZ-Set-New-Hot/123860910294
• Drive shaft for the impeller is a 4mm hex headed bolt; which press fits into the impeller
• Pump lid or cover has hex recesses in it as well. Use 5/32″ brass nuts pressed in as bearings and drill them out to 4.5mm
• Coupling for motor to drive shaft is a solid brass one off eBay, like this one.
  https://www.ebay.com.au/itm/5Pcs-Bass-Motor-coupling-Motor-Drive-Shaft-Coupling-Coupler-Connector-Sleeve/113961381587?hash=item1a88a0aed3:m:mAyGtqxiGOuKpDrUEzpXsjQ
• Print with 1.2mm shell (4 layers) and 30% infill
• No support, except for pump housing
• No brim or raft needed, unless you have warping problems