Centrifugal Pump,almost From Scrap!

About: Mad genius!

In general,i made this pump for one of my wacky projects.I've tested several variants,but this was the most successfull.The flow is about 160 l/h ,which i think is good for something built from scrap ;).It is a centrifugal pump (see http://en.wikipedia.org/wiki/Centrifugal_pump for more information),running on 12V ,from automatic screwdriver battery.The construction is pretty simple,and took about 15 minutes to build it.So let start.You will need:
-a piece of soft ,yielding plastic (for the impeller)
-two caps from carbonated drinks for the body(Coca-Cola for example)
-few long sticks to support the body to the DC motor,and one for the impeller's shaft
-one DC 12V (or so) motor,from an old cassette player.
-small piece (4-5mm) of wire insulation (for the connection between the impeller's shaft and the motor shaft)
-20cm of soft 6mm dia PVC hose
-hot glue gun
-1mm drill bit
-some patience,and itch ;)
P.S-The design is not very beautiful,but it works ;).Oh,and sorry for the bad english :oops:

Step 1: Making the Pump's Impeller

The impeller consists of 3 blades,glued on circular disc.These all are made of soft plastic.The next step is to glue the blades to the disc,using hot glue.The trick here is how are you going to position them-my motor runs only to the right,so the curved side of the blades,needs to be directed by this way,if your motor is running to the left,the curved side of the blades,should face to the left.After glueing,you should get something like the last picture of this step.

Step 2: Making the Upper Part of the Body,and Put the Impeller Shaft

As i mentioned in the first step,the body is made of bottle caps.The upper part is the one of them.It has one hole in it's center,where the impeller's shaft goes in,and one on it's side,where the pumped water comes out.The shaft's hole is 1mm wide,and the other is about 3-4mm.The next step is to glue the impeller's shaft to the impeller.After thaht,you get something,like the last picture.

Step 3: Put the Body and the Impeller Together

Now,lets put some parts together.Put a little washer on the impeller's shaft,and put it in the shaft's hole on the top of the cap.Now drill a hole in the other cap,and cut a little outlet on it's side like you did to the other.Put the second cap on the first ang lue them together.

Step 4: Connectig the Impeller's Shaft With the Motor

Get a little piece of wire (about 3-4mm) insulation,with apropriate diameter and put it on the motor's shaft,then put in the other end the impeller's shaft.Now put a little hot glue in the ends of the insulation to glue them to the shafts.

Step 5: Put the Supporting Sticks

Now it's time to put the supporting sticks,which holds the body to the DC motor.They are facing one against the other.Glue them so that the body is vertical not tilted (like mine :oops:)

Step 6: Final Step:glueing the Pvc Outlet Hose

Now it's time for the final step.Take the hose and put it that way,like it is coming out of the body,in the direction of motor's rotation.Glue it well and voila-you got a homemade pump from scrap!.That's all.Good luck,and take your life-belt before building this :P



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    8 Discussions


    7 years ago on Step 6

    Would be really interested to see if anyone has built something like this, but suitable for boiling temperatures, would be great for recirculating hot wort in a home brew situation. Could even be magnetic drive in same style as stir plates?


    8 years ago on Step 6

    no video showing an operation?


    9 years ago on Step 6

    you should post a video of the pump in action. id like to see how wellit works so i can tweak it as i make my own.


    9 years ago on Introduction

    This design was from a youtube video, by user; Forssa1 Please credit your sources, that is unless you posted that video.


    9 years ago on Introduction

    Not very much.Without the hose (which i have messed a little bit :oops:),maybe about 60-70cm or so.With the hose,it's less,but that is because,i didn't put it in the right place.I belive,that with higher RPM motor,it would create more pressure => the flow would be greater,and it would pump the water higher.I mean for example 3V DC motor from car toy or so.Mine is from old cassette player and that so it has lower RPM.

    1 reply

    Reply 9 years ago on Introduction

    Thanks, I'm a bit surprised at 160 Lh-1 as it works out at 44 mLs-1, I find that hard to believe (16?). I should have asked about height, pressure, priming specifically.



    Reply 9 years ago on Introduction

    Or, to clarify lemonie's question a little, how high can it pump water and maintain a decent flow rate? How high was it pumping the water when you measured 160L/hour? I like your shaft coupler as well, that's a neat trick on its own.