Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Hi Guys,

Just thought I should provide a quick update on the super bubbler
project - works great!

Total etch process...

Print layout on Dell Catalog pages using HP Laser 6P printer
Soak in water for a minute, rub off paper
Touch up specks along edge of board - good elsewhere
Drill two holes for hanger wire
Drop in tank with bubbles going
Go into office to get stop watch to time it
Come out and nearly half done on etching - didn't start watch
Total etch time 3~4 minutes give or take a minute

The etchant is a brand new batch of Ferric chloride mixed up this
morning. Temperature of shop at time of etching was about 85
degrees F.

Etching was fairly even - more so that with old bubbler stone and
fish tank pump. MUCH FASTER, at least 4 times faster, perhaps even
more.

Interesting observation was the bubbles and splatter. WIth the
little fish tank pump, I would almost always get a foam on the
surface. These little bubble would pop and spray a fine mist over
the work area. This system is using big bubbles and they don't seem
to throw the mist as far. As this is new etchant, this could
contribute to that effect. As the etchant ages, it may foam more so
I will watch for this.

The Dell catalog pages worked perfectly for the transfer. Only the
edges of the board needed a bit of touch up. This could be that the
paper was trimmed a tiny bit smaller than the PCB. No pin holes
anywhere in the transfer or etching.

So, I suspect good agitation really speeds up the etching process -
A LOT!

Chris