Cleaning Metal Threads

[Rebecca Tinkham <r_tinkham@xxxxxxxxxxx>]

Hello all,

I am working on an early twentieth century military uniform with tarnished
metal wires on the epaulets.  The epaulets, which can be removed from the
rest of the uniform for cleaning, have silver and gold plated copper alloy
(possibly brass) threads couched down with a waxed cotton thread to cotton
velvet, wool, and a stiffening fabric.  The silver metal is black and the
other metals have a greenish corrosion product on the surface.  I would like
to brighten the metals and remove some of the loose surface corrosion
products.  The threads and fabrics are all in good condition.

After reading through various approaches for cleaning metal threads, the use
of a water, perc., and non-ionic emulsion with a soft brush described by
Timar-Balazsy and Eastop or an electrochemical method seem to be gentle to
both the metal and fabric elements.

I would like to know what experience other conservators have had using these
approaches.  Were you happy with the cleaning achieved?  Did you see any
kind of redeposition back onto the metal or fabric?  What, if any, long-term
affects have you seen to the metal or fabric elements?

Thank You,

Rebecca Tinkham
Conservation Department
Museum Services Division/DCA
P.O. Box 2087
Santa Fe, NM
87504-2087
rebecca.tinkham@xxxxxxxxxxx