[ARSCLIST] using lacquers

[George Brock-Nannestad <pattac@xxxxxxxx>]

From: Patent Tactics, George Brock-Nannestad

Hello,

the two short video features on lacquer manufacture, record cutting, and 
galvanic processing/pressing are very instructive and honest. 

In the first, we can understand why a lacquer is so expensive: it is slow to 
manufacture and the reject rate is 50%. I use TRANSCO myself. There used to 
be talks about "spring" and "autumn" lacquers, the first being quieter. This 
has to do with temperature and humidity during the drying by evaporation that 
we see. Many different methods of depositing the nitro-cellulose lacquer have 
been tried, and no doubt at some stage controlled-atmosphere drying could 
have been introduced. Working dust-free would also have prevented the 
rejects. However, the whole technology was superceded by error-correction 
codes making dust specks irrelevant in the digital domain.

In the processing we see something very interesting: they are preparing an 
original metal negative, a "father", but they call it a stamper and use it as 
a stamper. This is something you would only do for small runs (I suppose most 
modern vinyl record production is small run), otherwise you would go the 
whole process of making a metal positive, "mother", and only from that make 
the stamper, the "son". Here, you would have to go back and cut another 
lacquer if you needed to exceed the print run of the first stamper; the 
matrix number scribing would be different, and so you would easily be able to 
distinguish between print runs.

I have a small story from real life to end this comment with:

you know that I have made a fair bit of research into the physical marks on 
78s that have a discographical bearing. For instance, in Europe we have been 
blessed with a lot of original scribed under-label information from Victor 
(acoustic and electrical) on the Gramophone Company (and later some 
Electrola) pressings, because the presses were different, and the whole metal 
surface was more or less used right through to pressing.

Now, I have in front of me a Danish shellac pressing, early-to-mid 1950s, 
Pathé PT1005; one side being "Liebeslied (Valse)" (Kreisler-Arrang. A. 
Bernard), Armand Bernard et son orchestre á cordes, matrix no.CPT 9407-21. 
Under the label it says "Made in France" in elevated reversed, which means it 
was stamped into a negative. Near the centre is the familiar AUDIODISC logo 
(which means they were not using PYRAL), but there are no holes for a drive 
pin. However, on the same circle as AUDIODISC it says: USE OTHER SIDE. 
Tableau!! There may be many reasons why they disobeyed this advice, but 
imagine that they advertise the fact! Possibly they had had to reject the 
"good" side and lacquers were - as always - expensive.

Kind regards,


George


Kind regards,


George