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Subject: Re: [Homebrew_PCBs] Re: ETCH TANK'S [COST EFFTIVE]

From: Stefan Trethan <stefan_trethan@...>
Date: 2004-04-10

On Sat, 10 Apr 2004 18:44:41 -0000, Phil <phil1960us@...> wrote:

> That's not a bad solution at all. What's the capacity of the tank
> (both in terms of etchant and size of PCB)? I couldn't find anything
> that held 1 L (or quart), would etch a 6"X6" board and was at least
> 8" deep (to hold the tank heater). They usually held 2 or 4 quarts
> and I didn't want to have that much etchant at a time.
>
> For me, that forced the inside dimensions of the liquid volume to be
> 8x7x1.25. The heater and air tube displaces enough to take it under
> a liter.
>
> By the way, Circuit Specialists has a kit that looks good for $40.
> It includes the tank, heater and air pump. http://www.web-
> tronics.com/lowcosetsysw.html If I were to do it over, I'd probably
> buy it instead of make my own. I spent about $30 on mine and took a
> few hours to do it. I dont believe their 4 minute etch time claim
> though...
>

I consider making one of glass...
I would get the glass for free, plexiglass not.
I reckon gluing with silicone glue on both sides would be a good idea.

It would be placed inside another container which could hold everything
if there is a leak or breaking.

The lid would be made of plexiglass.
I guess a bead of silicone, then a piece of thin plastic, then press the
lid on to form a good seal.

Thanks for all the suggestions about he tank, but most
of them are not exactly what i want to do.
i want the perfect tank (like always) with no mess, no "dead" space on the
pcb due to covering by clamps, no touching of immersed parts while
loading/unloading,
maximum of possible area possible, fully adjustable to all sizes.

Like always i try to make the impossible.....

ST

P.S.: haven't told you about the hot air pencil i tried to build.
the damn heating element was defunct and i had a little tabletop fire..
but gladly i plugged it at the isolation transformer so no harm done.
I tried to use an old soldering iron, should have tested it before.

Will make a new one when there is time, but different, a small copy of the
heat gun i have using a ceramic heating chamber which holds the heating
wire
and provides enough surface area. this time i will aim for a 50V unit so
that
no proper isolation is required. i can make a simple temperature control
circuit
with a thermistor and a scr.
still have to look if i can find a proper ceramic body to hold the wire, i
guess
a old "radiation heater" will do the job, chop of a bit of the ceramic
element.
, or maybe just a number of those small cermic isolation beads will do....

I hope to end up with something that is a bit better suited for small smd
work,
the steinel gun is very nice a tool and i use it often but it is cumbersome
and heavy to use for small things.