Hello readers this is a small project I had done over the weekend. I needed a magnatic stirrer at work, but because of some circumstances we couldn't order one. So I thought why shouldn't I build one by myself. I designed this thing with Inventor 2018.

This kind of machine is used in laboratories for mixing two or more seperate substances in a long time span. But you can also use it for removing PVA from your 3D printed parts. PVA is a water-soluble support material. It is used in dual or multi material 3D printing to have a cleaner end result. Sometimes the removing process can take very long. And for this reason I use the stirrer to get some movement in the water to remove the PVA faster also at places where I can't get easy acces to.

Step 1: What Can It Do?

Video

Step 2: What Do You Need?

2* M3 Nuts and Srews

2* M2 Srews

4 Magnets

3D printed Parts:

Step 3: 3D Print the Main Body

An important thing for me was that you can print this thing in one part. So I had to design a small overhangs. You have to use an oritation with the hole down and support. You should use the support setting Touching Buildplate and Slicing Tolerance to Exclusive (cura).

Cura Settings:

Support setting: Touching Buildplate --> That you only have support in the middle hole.
Slicing Tolarences: Exclusive --> That you don't get a hole in the shell because the shell isn't very thick.
You can use any kind of layer height, becasue it doesn't matter pretty much. I used a layer height of 0.3 because I want it to finsish within the weekend.

PS: My Ender 3 finished the print with no problems;)

Step 4: Srew the Motorcontroller

Put the nuts in the two slots. It can be very tricky to put the srews in, so take your time. And when I mean tricky I mean half a hour for two srews. But it isn't impossible.

Step 5: Put the Magnetic Spinner In

First put the spinner with the magnts glued in place in the hole. Use hot glue for this. Than take you fingers and press it down so that you can press the motor from the other side threw the hole from the bottom. So now you take some tape and tape the srew to the srewdriver, because if you don't do this you won't have chance to fix the screws. The magnet will always push the magnets out of your controll. But the tape allows you to finish this in two minutes. If the screw sits in the thread pull ou the tape. Then solder two cables to the motor and srews them at the motor-controller srew terminals.

Step 6: Put the Poti In

Remove the poti cap. Put the poticonnector in the motorcontroller and press in the hole at the inside. Than take the cover and put it again back on the poti. The poti will hold without glue, because of the small hole in the inside.

Step 7: (Optional) Scalar

A small scalar to show on which speed the poti is put on. Print the file "Symbol.docx" and cut the cicle carfull out and also the inside. Than take some transparent tape and put it flat over the complete cicle. Now cut the transparent tape slitly larger then the paper circle and glue it on the man body like shown in the picture.

PS: In my case I didn't really care about the look of the tape. Maybe you can do better than me ;)

Symbol.docx
Download

Step 8: (Optional) Bottom Feed

This little border will help to reduce the noise and the vibration. It is a TPU part so keep in mind that not every 3D printer can print with TPU.

Step 9: Conclusion

Check out my video to see the spinner at work. It was a really cool but challenging project for me. I learn a lot and I hope to be able to use this knowledge in future projects. I hope you enjoy this Instractable and have fun to build it. Let me know in the comments what you think or if you have any questions?

Thank you for reading.