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.