I totally agree that the best solution is an etch AND storage tank,
all in one.
Unfortunately, m tank is plastic. I (currently) use AP. I have
heard anecdotal evidence that it eats plastic so I dont want to store
it in the tank. I've kept my eye out for a glass tank but they are
all too big (4 L/1 G) and I want to only have 1 L of etchant for
safety sake. I guess at some point I'll build a glass one if I dont
find a suitable container.
--- In
Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
> On Mon, 09 Aug 2004 14:23:55 -0000, Phil <phil1960us@y...> wrote:
>
> > that's not a bad idea at all for etching though I'd be very
careful
> > even with double bagging. Its a good, cheap way to do quick one-
off
> > etches. Even allows for aggitation though I'd be reluctant to
handle
> > a full bag.
> >
> > Still, I prefer the tank I made which has a bubbler and heater.
> > Yeah, its more "stuff" and requires cleaning but I get very
> > consistant, even etching and can do multiple boards at once.
Pouring
> > etchant back into the storage container is very precise. I'll
stick
> > with it.
> >
>
> Phil, the trick is to make the container in a way so that almost
> no cleaning and no pouring back for storage is required.
> (Though i doubt emptying and discarding the bags is less hassle
than
> cleaning
> your container)
> I have a glass tank for CuCl, which holds one liter and can do
boards
> approx. 30cmx20cm.
> I keep the etchant in all the time (silicone adhesive seal for the
lid),
> if i need a board i lift the lid, clamp the board in the holder,
put it
> back in, etch.
>
> (note: not touching any "wet" internal parts while doing that, the
board
> clamp is "remote controlled" through the lid and operated by the
thumb of
> the hand holding the lid while the other
> hand positions the pcb)
>
> When it is ready i lift it out by the handle, position it over the
water
> container, and push
> the "remote control" for the clamp mechanism. the PCB is released
and in
> the water.
>
> You see, not a drop of etchant is wasted because ONLY the PCB can
carry
> any etchant on it's surface
> and is washed. the other parts never touch anything, and never get
cleaned.
> It is also sealed off enough so that closeby tools won't corrode.
> The whole tank sits in a plastic container but there were no leaks
so far.
> The nice thing is you can clearly see both sides while in the
etchant, no
> need to pull it out
> to see if it is completed. I have a hydrometer in there to see the
density
> (CuCl), and
> also a electrolysis setup with carbon electrodes, but i didn't fire
it up
> yet 'cause i
> think it isn't really useful. I could easily add a bubbler and
heater
> because the last 5cm
> on both ends of the lid are separated and can be used to carry a
hose, a
> heater, or like it
> is now carbon electrodes. I don't want a bubble because of the
possible
> fumes.
> However, speeding it up is easy by adding mechanical agitation. A
geared
> motor
> "sways" the holder from side to side (the silicone seal allows
that) and
> does
> speed up the process a lot.
>
> Best part: building was basically free, i had the glass and the
lid/holder
> is made
> of old printer chassis. The slicone adhesive is the only cost.
>
> I can only suggest to go on and build one, it is a big difference
if you
> have to prepare
> your "bowl" and storage bottle, handle dangerous chemicals, or just
open
> the lid and put
> it in there without getting your hands dirty.
>
> ST