Homebrew PCBs

I don't use any chemicals to clean my PCB panels.  I use Scotch-Brite 
pads and dish soap & hot water to clean my PCB panels before putting 
the toner pattern on them.

I like the Red Scotch-Brite pads better then the Green ones, as the 
Red pads are a bit more aggressive then the Green ones - and the Red 
pads seem to last longer.

The Scotch-Brite pads scuff up the Copper just enough to provide some 
roughness, allowing the toner to adhere better to the Copper, but 
also causing no distortion to the toner pattern when it's fused to 
the Copper.

I use dish soap because it is specifically designed to cut grease & 
oil, which is what you want to get good fusing of the toner to the 
CLEAN Copper.

I use as high a water temperature and I can tolerate, as this helps 
the PCB blank to dry as quickly as possible, helping reduce 
oxidization of the Copper.  A clean bath towel to Pat the blank PCB 
down with also ensures no oxidization and Copper discoloration occurs.

I try to fuse the toner pattern to the freshly cleaned PCB blank 
within a few minutes, and then get the patternized PCB blank into the 
enchant as quickly as possible, also reducing any chance of 
oxidization and Copper contamination.

Further, I don't touch any exposed Copper area with my fingers after 
I've cleaned the surface of the blank PCB panel, as the oil from ones 
fingers will prevent the toner from adhering to the Copper, as well - 
always hold the prepared PCB blank by it's edges.

These are some of the things that I've learned and use over the past 
10 years or so of using the Toner Transfer method of applying artwork 
patterns to Copper clad PCB material.

I hope it helps...


--- In Homebrew_PCBs@yahoogroups.com, "pork_u_pine2000" <wittend@...> 
wrote:
>
> --- In Homebrew_PCBs@yahoogroups.com, William Alford <walford@> 
wrote:
> ...
> > 
> > Don Lancaster, famed electronics writer online at the guru's lair 
has 
> > said that after chemical cleaning, the board should be quickly 
dipped 
> > into ferric chloride and then well rinsed before beginning any 
kind 
> > of PC resist coverage. 
> 
> ...
> 
> > 
> > William Alford
> > 
> > GI Motility Medical Research Page
> > http://alford.grimtrojan.com/ 
> > 
> > [Non-text portions of this message have been removed]
> >
> 
> Yesterday I was working on some small urgently needed boards using
> toner transfer and my usual methods.  Everything went well enough
> until i ran out of fresh board material and needed to reuse some 
that
> had been used for an earlier, incorrect pattern.  
> 
> Suddenly, though I cleaned with 91% IPA, then Acetone, then Toluene,
> used Scotchbrite and Bar Keeper's Friend copper cleanser, one at a
> time and then in combinations, I could not get acceptable toner
> adhesion.  
> 
> In desperation I put the cleaned board into the ferric chloride for
> just long enough to see a patina.  It wasn't pretty - the slight
> whorls and general unevenness in the copper's color made me uneasy
> about trying this.  But after that things went much better, and I
> finished the project.
> 
> Like traditional photography, the limitations one has on process
> control makes producing small quantity PCBs a challenge, and 
sometimes
> something of a mystery.
> 
> Dave Witten
>