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