Print

Print


Dear George,

Like so much concerning our area of interest, the information is not
documented. My knowledge comes from conversations over the years with
veteran studio engineers, who at various times individually corrobarated
the details posted earlier.

DDR

On Wed, Feb 29, 2012 at 10:34 AM, George Brock-Nannestad <[log in to unmask]>wrote:

> From: Patent Tactics, George Brock-Nannestad
>
>
>
> Hello Dennis [Rooney],
>
> you wrote
>
> > Although the first instantaneous blanks were cellulose nitrate, the
> > formula was later changed to cellulose acetate, hence the use of
> "acetate" as a
> > cognomen for discs which are properly called "lacquer(s)". The change was
> > prompted by some unfortunate accidents involving mastering engineers who
> > smoked while cutting lacquers. The vast majority of surviving lacquer
> > discs are cellulose acetate. No worries (at least not about
> combustibility).
> >
>
> ----- now, I have been chasing information like that for quite some time.
> Could you quote some sources, please? Newspaper reports are fine, but
> technical litereture would be better. The only reference to non-inflammable
> acetate lacquer discs I have been able to find concerns home recording
> discs
> from ca. 1938. All other sources, in particular for professional use, have
> referred to nitrate as the major constituent.
>
> The reason there is no need to worry about your lacquer discs in the
> archive
> is -- as Steve Greene surmised -- that the volume of nitrate to cooling
> carrier ratio is so small. Just like Blue Amberols. The reason mastering
> engineers sometimes had fires was 1) they were not using vacuum for
> removing
> the swarf and were careless, 2) if they used vacuum, as was the
> professional
> way, they deliberately set fire to the content in the can for swarf - wax
> was
> just as inflammable, and if you light steel wool it will continue to
> smolder
> until it is all iron oxide - it is the fine division that gives the
> problems.
>
> Best wishes,
>
>
> George
>
> -----------------------------------------------
>
>
>
> >
> > On Wed, Feb 29, 2012 at 9:20 AM, Steve Greene <[log in to unmask]>
> > wrote:
> >
> > > Hello,
> > > First time poster here.  How big a concern is the storage of
> > transcription
> > > recordings, a majority of which are made of coated cellulose nitrate
> > > lacquer? Coming from a moving image background, the "n" word (NITRATE)
> > is
> > > scary, though presumably the volume of nitrate in even a large
> > collection
> > > of coated discs is tiny compared to even a small collection of nitrate
> > > film.  Were there components in the "recipe" for nitrate lacquer that
> > > tended to make them less combustible?
> > >
> > > Thanks in advance for your advice, perspectives.
> > >
> > >
> > >
> > >
> > >
> > >
> > > Steve Greene
> > > Archivist
> > > Office of Presidential Libraries
> > > National Archives and Records Administration
> > > (301) 837-1772
> > >
> >
> >
> >
> > --
> > Dennis D. Rooney
> > 303 W. 66th Street, 9HE
> > New York, NY 10023
> > 212.874.9626
>



-- 
Dennis D. Rooney
303 W. 66th Street, 9HE
New York, NY 10023
212.874.9626