Overcoating suggestion:
I've started using "Future" acrylic floor wax to prevent the copper traces
from oxidizng. Just wipe a thin film on and let it dry. Soldering though it
is no problem.
TANSTAAFL!
Myc
On 7/13/06, Stefan Trethan <stefan_trethan@...> wrote:
>
> On Thu, 13 Jul 2006 03:13:43 +0200, warrenbrayshaw
> <warrenbrayshaw@...> wrote:
>
> >
> > I have always used Shellac to protect the newly etched PCB. Shellac is
> > made by dissolving commercial Shellac flakes in methylated spirits.
> > French polish is the same thing. Also I have a tin of product from the
> > hardware store and it is known as "Patent Knotting."
> > The Shellac goes on the colour of varnish and prevents oxidation and
> > can be soldered through. It appears to react like a flux when soldering
> > through it.
>
>
>
> I use colophony resin. Basically tree resin with the turpentine removed.
> It's the same flux as used in rosin core solder wire. If given enough time
> to dry a laquer made of this will be dry and hard to the touch, although
> it does stay sticky longer than normal laquer (i believe this may be
> caused by water in the impure alcohols). It protects against corrosion,
> and acts as a flux during soldering. While it may not be ideal for the
> highest impedance circuits i have not had any problems so far.
> I used (and still use) a ready-made spray can version of it, but i spotted
> colophony chunks at the chemicals shop, very good almost transparent
> quality. The lighter in color it is the lighter the flux residue will be,
> the dark brown stuff looks awful after soldering. The chunks can be solved
> in alcohol just like shellac to make a laquer.
> I've also molten colophony into the little compartments at the end of my
> solder spool (the compartments to keep the plastic stiff). It's great to
> help with tinning wires.
>
> I always thought shellac is a tree resin, but now i looked and it is
> actually produced by a beetle. I had no idea..
>
> ST
>
>
>
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>
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