At Tue, 8 Jan 2008 11:23:52 -0500,
David Lennick wrote:
For starters, the only 78s that are truly unbreakable are the ones made
for mood music libraries (Chappell, Boosey & Hawkes et al) in the 50s
and Capitol's "Superflex" kids records in the 40s. Everything else can be
cracked by putting your thumbnails together and pushing up..
experimenting this way on unwanted discs is a good way to learn which
ones will and which ones won't. Even Decca LPs from the mid 50s to
the early 60s will fail this test.
Other than that, it may be a matter of what country you're in.
Canadian plants kept 78s into 1960 and all but Quality used shellac,
while Quality's vinyl was easily cracked.
At Tue, 8 Jan 2008 13:27:09 EST,
Dnjchi@xxxxxxx wrote:
I've seen some postings suggesting styrene rather than vinyl.
More brittle, I believe.
Hmmm, so there is a strong possibility that
early "non-breakable under normal use" 78rpms are not made of
vinyl but other materials like styrene?
I have also seen somewhere such 78rpms are made either of styrene,
or of vinyl whose percentages of materials are different from
that of later flexible vinyl 78rpms/LPs.
Anyway, is it possible that the "non-breakable" 78rpms (not
thin and flexible 78rpms) uses the same materials as early thick
LP records?