I'm not convinced those slots will be small enough to prevent the vapor
coming out when the bubbler is on.
I see what you mean, my idea for the moving tube is because i would like
to keep it fairly low in height so the tank mustn't be enlarged much. If
one would be able to get a small number of holes working uniformly the
length you need to move the nozzles would be reduced. I don't think it
much of a problem to make a magnet slide around outside the tank...
Anyway, if you make that pendulum, why not attach soft plastic brushes
that brush the board? might be more uniform, and the wiping action surely
mixes the etchant well enough. If the brushes were moved with magnets one
could put a windscreen wiper assy outside the tank, or something similar.
I'm not gonna try that any time soon, since my setup is just too simple
and too well working to change. Even the thought of making a PCB holder
that holds the board firmly enough to allow brushing seems way too much
work to me.
ST
On Fri, 23 Dec 2005 13:17:09 +0100, Alan King <alan@...> wrote:
>
>
> But that will require something else to do moving, and rotary to
>
> linear motion.
>
>
> Tank, then a pole on the outside center of the long side of the tank,
>
> that's 2x the height of the tank, so the hinge point is at 1x more above
>
> the edge of the tank. Longer arm to make the sweep at the bottom more
>
> linear. Say a 1.8X arm, with a stone at the bottom, and air tube to the
>
> stone. Driving link and motor attach near the hinge, well out of the
>
> etchant. Use a flat arm, flatten the tube a bit as it passes the lid,
>
> and have a decent raise/lower system for the board, and you can leave a
>
> top on the tank. Just a slot for the arm/tube to sweep, and a slot to
>
> load the board through.. Clear PVC etc on each side of those slots, to
>
> close it except when the arm or board are right there, and you will have
>
> near zero evaporation, and almost never open the container. Just slot
>
> load the board and etch. No tube thing to build, just get a stone and
>
> some line and make a fairly simple pendulum and attach a motor to it.
>
> Can be greatly linearized with a little mechanical mixing, or a stepper
>
> etc could make it near perfectly linear. So simple we should have come
>
> up with it talking about the rotary etcher and other types last year,
>
> duh if a stone is too uneven sitting there then move it.. Obvious
>
> concept, just didn't even cross my mind at that time..
>
>
> Wait till you see some video of my little manufacturing plant for
>
> rounding my boards and applying the LEDs, I think it's rather neat..
>
> So nice to have all the flying dust stay inside a ziplock bag.. Now to
>
> automate my iron and solder feed and feeding the LEDs, may as well let
>
> it build the board for me while I go have a beer.
>
>
> Alan
>
>