Homebrew PCBs

>i think your pump principle is like those medical "silicon hose rotrary 
>pumps".
>they are used for pumping blood and other liquids.
>the advantage is the silicone hose can be replaced easily, making 
>sterilization
>unneccesary, the expensive pump motor, casing etc. is reused...
>
>i have no idea where a rc plane builder may need such a pump (i'm kind of 
>involved
>in that now...). maybe for tank refueling on glow engine planes (i only use 
>electric power).

Yep, tank refueling is what they are used for.

>but i think this is not a pump for spray etching, it it a slow pump.

Would that not change if a motor is used? The tube could have a
dameter of say 1/2" and this would transport quite a bit of etchant in
a short tim - no? I can imagine that such a pump could do but then I
don't have experience with pumps. It just apealed me because they seem
to be easy to build and - based on their principle of operation they
of course also would resist the etchant.

Markus