Homebrew PCBs

From looking at this graphic on their website: (bottom one)
http://www.bungard.com/material/left_4.gif

It appears that the ethchant is drawn up into the tube
by vacuum pressure. The squirrel cage fan on top
would suck out the air when the tube spins.
I can't imagine how the etchant is prevented from
spraying out of the top though.... I guess there must be
some sort of barrier that lets air through, but
prevents fluid from doing so. Or, it is possible
that the fan is also housed within the splash tank.

Anyone know of a source for all plastic or stainless
steel squirrel cage fans? 

~Rolan

--- In Homebrew_PCBs@yahoogroups.com, adam Seychell
<adam_seychell@y...> wrote:
> That's an interesting mechanism of pumping fluids. After 
> Markus mentioned Bungard and patents I had a quick search
> The bungard site is http://www.bungard.com/seiten/home.htm
>