Homebrew PCBs

Just an idea for pumping etchant...

What about a peristaltic pump?
The ones I have seen use a silicon rubber tubing and good for all sorts  
of fluids.


Simon Whitehead

On Tuesday, Apr 22, 2003, at 10:45 Europe/London, Leon Heller wrote:

>
> ----- Original Message -----
> From: "Stefan Trethan" <stefan_trethan@...>
> To: <Homebrew_PCBs@yahoogroups.com>
> Sent: Tuesday, April 22, 2003 9:59 AM
> Subject: Re: [Homebrew_PCBs] Re: Cu + HCl -> CuCl2 : part 3
>
>
>> I'm wondering if anyone has thought about spray etching...
>>
>> this may give uniform etch, may be very fast and may also regenerate  
>> the
> etchant.
>> but i have no idea if you can prevent a cheap pump from being eaten  
>> away
> soon.
>> the plastic pumps i know have a permanent magnet exposed to the fluid  
>> as
> rotor. and i believe nylon
>> bearing.
>> but this may also be too complicated and even dangerous (etchant  
>> jet...)..
>>
>
> I think that spray etching is used by most of the PCB manufacturers.
>
> I've often wondered whether ultrasonics would be useful. We used  
> ultrasonic
> cleaning where I worked many years ago with very high-power units. The
> cavitation  produced on the surface of the copper should give very  
> rapid
> removal. The effect of the etchant on the transducers needs to be  
> solved, of
> course, perhaps by coupling them to the base of the tank, so they  
> aren't
> exposed.
>
> Leon
> --
> Leon Heller, G1HSM
> leon_heller@...
> http://www.geocities.com/leon_heller
>
> ------------------------ Yahoo! Groups Sponsor  
> ---------------------~-->
> Make Money Online Auctions! Make $500.00 or We Will Give You Thirty  
> Dollars for Trying!
> http://us.click.yahoo.com/yMx78A/fNtFAA/i5gGAA/bGYolB/TM
> --------------------------------------------------------------------- 
> ~->
>
> Be sure to visit the group home and check for new Bookmarks and files:
> http://groups.yahoo.com/group/Homebrew_PCBs
>
> To unsubscribe from this group, send an email to:
> Homebrew_PCBs-unsubscribe@yahoogroups.com
>
>
>
> Your use of Yahoo! Groups is subject to  
> http://docs.yahoo.com/info/terms/
>
>
>
>
>
Simon Whitehead
4 Colleton Crescent
Exeter
Devon EX2 4DG
England
01392 217873
s.whitehead@...