That's good you put that up Smitty, inspired me to explain how I make them 
supplementary to your link <g>.
If I knew how to put a photo of mine on here I would, but I got this from ideas 
in the public domain, and there's pictures available as well if one searches 
DIY mag stirrers.
I use kids jewellery boxes, they have a draw for stir bar storage as a 
bonus.Open lid and rip the mirror off, and everything else out of the top 
shelf.Cut hole in lid big enough for computer fan to be fixed underneath.Cut 
the plastic speaker cover from old radio or whatever and fix that on lid top 
covering the hole above fan.Wire an on/off switch connecting the fan, the 
switch and a power adaptor plug fixed to the box and that's pretty much it.
Computer fans are 12vdc so if one can get a variable voltage power adaptor 
which can be lowered to lowest voltage setting to keep stir bar spinning you've 
got a magnetic stirrer.
All you need is a hole saw for the lid, some soldering practice, some wire and 
switch etc.
Dead simple to make and works a charm for me.
N.

Date: Thu, 29 Nov 2012 11:13:04 -1000
From: papad...@gmail.com
To: silver-list@eskimo.com
Subject: CS>magnetic stirrer

Here's a project for the do-it-yourselfcraftsmen. Haven't built it, just 
passing on.Smitty
http://tinyurl.com/blu6f73