gEDA-user: experiences using geda with students

[John Griessen]

Karel Kulhavy wrote:

>> Here's a board etched with it:
>> http://shop.cottagematic.com/elab/etched-board-epson-photo-paper.jpg
>> This photo was out of focus, but it's easy to see in a bubble tank when 
>> laminate substrate is showing   --  copper can still be seen on the bottom 
>> edge. http://shop.cottagematic.com/elab/etch-done.jpg
> 
> What are the black stains? Places where the patterns were accidentally
> etched through? Or some kind of corrosion?

[jg] Those are places where the adhesion of the transferred toner was imperfect 
and it shows copper oxide black color.  Those places did not etch much though. 
I may need to add a scrub with some acid cleanser before soldering or 
electroless plating.

> 
> Is it a picture taken during the etching process or after?
[jg] Pink copper with some black stains is after, Blurry green is during.
> 
> CL<


John Griessen