Al Wurth was the electroplating expert the laboratory and would have
supervised this work. Use EDIS 14425 through
14428. Use EDIS 23181 (copper
plated mold) and EDIS 24845
(copper master mold). The cylinder disc was placed inside vacuum and
small particles gold "spluttered" while the disc cylinder revolved. Attach vacuum pump. Use EDIS 376. Use EDIS 2077.
TOOTHBRUSHES, Used plating.
MOLDS, one copper-plated
and one copper-master (next
to wax master)
Complements artifact. The wax was removed and the surface cleaned. The result was a
perfect negative impression the recording groove, called matrix. Use EDIS 14330 through
14335.
Object and Location Evidence Recommendation
Table 2
LAB TABLE (in place) Figure 29. This equipment for disc records was successor the method
of gold plating cylinder masters that had been successfully developed the
laboratory from 1888-1903.
GRAPHITE (in six glass jars) Used plating.
Acquire.
EDIS collection reproduce.
Both these methods gave the surface the disc electroconductive surface.
The plating was done hard rubber baths with anodes inside them.
BRUSHES, (on table) Used clean wax from
copper surface.Table Electroplating Records. Use E-159-5. the
production process thin layer graphite was brushed onto the wax master.
ELECTROPLATING
DEVICE (on table)
Figure 29.
VACUUM PUMP (on table) Figure 29. The electroplating equipment shown this
table represents the method Edison devised make numerous duplicates of
master recordings.
WAX MASTER (in
electroplating device)
Complements artifact. This was
used the record press make duplicates.
KNIFE, sharp (on table) Used trim "flash," pieces
of material protruding over
the edges the mold.
208
. The master
was first copper plated, and then nickel plated top this thin layer form a
durable surface
