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Re: [ARSCLIST] Fwd: Sticky AGFA PEM 469
Dear Tom: Its Charlie, not Richard. The info on the Ampex 600 PVC
binder comes from recent massive multiple chemical lab studies I did
on various tapes, solving the sticky shed problem, and my new Rezerex
tape restoration process. It is the meticulous work of many years.
The PVC shows up in the chemical forensic studies of the Ampex 600
binder chemical in the chemical extraction and spectrum analysis done
under my
instruction and supervision at one of the country's finest chemical
laboratories. The source of the information is thus a chemical
laboratory report which remains in my private hands only as it is not
published publicly. This first report is about 1 and 1/2 inches thick
and is very technical.
There are other lab reports I have in hand. In all the various tape
chemical issues just about anything can be found out and known. It is
simply a matter of time, effort, and money being spent to get to the
chemical bottom of things. It is helpful to me to have both an
engineering background and also a chemical/scientific background to
frame the issues, problems, questions, and dig out the answers. The
Ampex 600 series of tapes has very unusual chemical behavior compared
to most others. I checked it out and found out why. A short answer
to a very long story.
Charles Richardson
On Apr 7, 2008, at 8:47 PM, Tom Fine wrote:
Hi Richard:
Please site your source for the Ampex 600 series story. Thanks.
-- Tom Fine
----- Original Message ----- From: "Charles A. Richardson" <charlesarichardson@xxxxxxxxxxx
>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Monday, April 07, 2008 8:06 PM
Subject: Re: [ARSCLIST] Fwd: Sticky AGFA PEM 469
Dear David:
Regarding the EPA, Whale oil, etc. In 1970 the EPA was created by
Congress. In 1972 the Marine Mammal Protection Act banned hunting
of whales and this was supplemented in 1982 when the UN also
passed an international whale hunting ban as whales were in danger
of extinction. Whale oil is a good mechanical lubricant and is
used in oiling precision mechanisms such as watches and clocks,
but it was never used as a binder lubricant in tape manufacture.
Chemical Engineering has synthesized whale oil so as to reduce the
demand for natural whale oil. There may be an after market
lubricant based on either natural or synthetic whale oil which
some use in attempting to "re-lubricate" a tape that has squealing
problems. It is a very limited band aide short term remedy which
is not approved by chemists as safe.
In 1976 the Toxic Substances Act banned the use of Polychlorinated
Biphenyl chemicals or PCB's. PCBs were used as a liquid coolant in
big
AC power transformers used by the electric utility companies.
PCBs were used in transformers, some motors, and some capacitors.
PCBs were never used in tape manufacture. There was a major
environmental disaster in the 1970s when companies dumped large
quantities of PCBs into the Hudson River and the James River,
creating a poisoned water environment that will take centuries to
remedy. Chlorine, and most of its compounds are dangerous
poisons, thus they are banned unless one gets a waiver and/or an
EPA license which can only be had by instituting
strict material use and disposal controls that met EPA chemical
safety standards.
PVC, Polyvinyl Chloride, was used in Europe for some time by BASF
and AGFA in the manufacture of their base films. Ampex used a PVC
binder, but only in their 600 series of tapes. There is a major
chemical problem with PVC. Any loose radical Chlorine atoms can
readily combine with moisture to form Hydrochloric Acid, or HCL.
When this happens, the HCL will attack the head core materials and
the tape head gaps, which drastically shortens head life and
causes major problems in the head gap area. So for both
environmental problems of handling Chlorine, and its bad habit of
generating HCL and eating tape heads, PVC was dropped from tape
manufacture, decades ago, with the exception of its continued use
for decades in the Ampex 600 series tape binder chemistry.
The seeds of the disaster that have lead to Sticky Shed Syndrome
arise in tape maker chemical changes of the 1970s, is an important
and interesting story. I do not believe that the government had
anything to do with these tape chemical changes. They were done
by tape makers for various reasons unrelated to government
regulation.
Hope this helps.
Charles Richardson
On Apr 5, 2008, at 6:25 PM, David Lennick wrote:
I will stand corrected if that's the case, but that was what I
heard at the time.
dl
Tom Fine wrote:
Hi David:
Are you sure the whale oil story is true. I was told it is
mythology and that the real story is that certain solvents
couldn't be used in the manufacturing process anymore.
-- Tom Fine
----- Original Message ----- From: "David Lennick" <dlennick@xxxxxxxxxxxx
>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Saturday, April 05, 2008 12:04 PM
Subject: Re: [ARSCLIST] Fwd: Sticky AGFA PEM 469
"Environmental law changes forced most tape manufactures to
change the
formula of their binder in the early 70's."
Read: They used to use whale oil, then they went to synthetic.