Homebrew PCBs

I am thinking of giving this a try.  Could you clarify about the Arm & Hammer Super Washing Soda mixture?  Is that 1/2tsp per 1 Cup of water?

--- In Homebrew_PCBs@yahoogroups.com, "timgmorris@..." <timgmorris@...> wrote:
>
> Sorry, haven't checked the list in a while. My source for the photoresist was http://www.digole.com/index.php?productID=228
> 
> The web store appears to be Canadian but the products come from China, so shipping can be anywhere from a week to a month.
> 
> It's a negative photoresist, so you need to invert the output of EagleCAD. I use Arm & Hammer Super Washing Soda as the developer (1/2tsp per 1C of water). I also use this resist as the solder mask, which works quite well.
> 
> Some pics:
> http://www.timtilities.com/index.php/electronics-menu/101-panel-2-pcb
> 
> --- In Homebrew_PCBs@yahoogroups.com, Misc Clark <clark.cone4@> wrote:
> >
> > Tim! what is the source of the A6 sheets of photoresist?
> > Curious in Charlotte
> > Clark Cone
> >
>