On Fri, 23 Dec 2005 15:34:50 +0100, lcdpublishing
<
lcdpublishing@...> wrote:
>
>
> There is a spinning magnent under the top surface of the machine.
>
> You place a beaker of fluid on top of that surface and turn on the
>
> machine and the fluid spins like crazy - very good fluid agitation
>
> without any mechanical connections or hoses etc. The things look
>
> neat as hell, but I have not idea what they are called or how
>
> exactly they work.
This is called a magnetic stirrer. You drop a magnet, often coated in
teflon, in the glass and a rotating magnetic field spins it. Often those
machines are combined with a hotplate.
Your expected drawbacks are probably why this isn't used very often for
etching.
ST