tinkerStirrer MK1, DIY high performance magnetic stirrer by tinkerheart

Last crawled date: 3 years ago

So, time to build some laboratory equipment. We have a microscope (http://tinkerheart.eu/tinkermicroscope/), but that hardly makes a laboratory. This time we’ll build a humble magnetic stirrer.
Many people have build magnetic stirrers, and you can find many tutorials online, but this is my way of building a stirrer. It features a tough (partial) aluminum shell, a 3800 rpm motor and neodymium magnets. The parts used are fairly cheap, but it is obviously possible to make a cheaper stirrer – I do however think I get a lot of stirring for my money with this machine.
A few words about safety: Neodymium magnets are not toys, they can attract metal and other magnets (no surprise) and they are brittle and prone to shattering on impact which can result in sharp shrapnel traveling at high velocity (possible surprise, also painful. And potentially blinding). So always protect your eyes (and other people’s eyes).
When sourcing materials there are a few things to be aware of. The fan I use can be purchased both as new and as refurbished – I recommend that you get new ones, as the quality of the refurbished ones varies too much to my experience. Also, when purchasing neodymium magnets the most common magnet strength ratings found on AliExpress are N35, N50 and N52 – sadly many sellers lie about the strength of their magnets since they know most people can’t measure the exact level of magnet strength, so do not focus so much on the strength rating, simply buy from a seller with good reviews.
3d printing advice
I printed my own machine parts using inexpensive PLA on a Prusa MK3S. Threaded parts should be printed at a layer height of 0.2mm or less. 3 perimenters and 10% or more infill works well for me.
How to build your very own tinkerStirrer
Please watch this movie: https://youtu.be/umn0Ur9iAJA
Other parts:
Please visit http://tinkerheart.eu/tinkerstirrer_mk1/ for the complete bill of materials.