On Thu, 24 Apr 2003 15:18:04 -0000, you wrote:
>>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.
No, you are wrong. The gyroforce resulting from the turning tube is
sufficient. The structure you refer to is exclusively here to cool the
motor.
>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....
Simple, the tube is not open on top. The only opeining are the holes
on the bottom and those along the tube. You actually refer to the
device from Bungard which I compared to the one from Radix GmbH.
> I guess there must be
>some sort of barrier that lets air through, but
>prevents fluid from doing so.
Again, no. The principle is genious and somehow selfcontroling. There
is never more etchant in the tube than what can left the tube through
the fine spray holes, in other words the level to wich the etchant
climbs is determined by the highest spray hole in the tube.
>Or, it is possible
>that the fan is also housed within the splash tank.
no
>Anyone know of a source for all plastic or stainless
>steel squirrel cage fans?
Again, a similar, much cheaper device can be bought from Radix.
Markus