Sometimes
a white residue appears alongside the solder bead sometime after a
piece is finished, covered in patina, and waxed. This seems to have
two causes.
First
- Residual acid
As
there is a possibility of some acid remaining on the piece, rinse
with a bit of bicarbonate of soda added to the water. This will
neutralise the acids from the flux and patina that may still be
lurking under the foil and solder beads. If you get a frothing while
cleaning with the soda, you will know there is still acid present.
Wash - rather than scrub - those areas again with the water and soda
solution until there is no foaming.
Second
- Trapped moisture
Moisture
can also produce this as it allows minerals to migrate from under the
solder seams. The advice seems to centre on cleaning. First do not
use much soap in the initial cleaning solution. After rinsing ensure
the piece is completely dry by setting it aside in a warm dry place
for a day or two before waxing or sealing.
Those
that use paste waxes seem to have less difficulty than those who use
thin or spray on waxes. The heavier waxes seem to seal any moisture
within the structure. The moisture seems to be able to migrate
through the thinner waxes. It is not optimum to have moisture sealed
within the panel, as it will eventually come through the wax as it
ages.
So
it seems the best long term result will be achieved by ensuring
everything is absolutely acid free and completely dry before waxing.
No comments:
Post a Comment