This thank you is to everyone that responded - I don't know why I didn't
think of doing an exposer test like that - guess it's just been a long
weekend ;)

I am in the process of etching a test right now with the hopes that it comes
back "ok" - a big part of the problem was my developer mix - it was way too
strong.  I weakened it to a guaranteed 9:1 mix (ie: I didn't eyeball it ;),
and it worked much better, albiet slower lol.

Mike - I do have a couple of questions for you though...

>
> -  At this point, I cover the PCB in aluminum foil to protect it from the
> light (probably overkill, but better that than *underkill*).  I make my
own
> developer using 1/8tsp lye (from the grocery store) per 3 ounces of tap
> water.  I do this because it saves me the headache of storing the
developer
> (stored developer must be protected from light, air, and is sensitive to
> temperature.  The developer is a little on the weak side, which means that
> it may take a little longer than it 'should' to develop, but for say, a
> 6"x4" PCB, it only takes about 2 minutes.

Are we talking just normal lye, like red devil lye?  Also, what type of a
container does this mixture need to be in?  Can it still be in plastic, or
are we up to glass only level now?

>
> -  More home chemistry...  To etch boards, I use a solution of 1 part 37%
> HCl (available as 'Muriatic acid' at your local home improvement store!)
and
> 2 parts 3% hydrogen peroxide (again from the grocery store), and agitate
> gently.  **While mixing and using the solution, proper ventilation is
> EXTREMELY important** (and someday, I will practice what I preach ;-)
>

This Muriatic acid - will the types for swimming pools work?  or are their
different concentrations available that I need to look for?

Also, disposal of this home brew etching material - how to do it?  I've
never had to get rid of exess muriatic acid before...

Also, what types of gloves do you use for handling?

Thanks in advance!!

-Tony

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