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Re: [ARSCLIST] Fwd: Sticky AGFA PEM 469

Hi Charlie:

Woops on the name, sorry about that.

Your comments about Ampex 600 series are very curious. Are you saying that this tape wears out heads? Or is your theory that some chemical in the tape can under certain circumstances wear out heads?

In the real (reel) world, Ampex 600 series was used by the millions of feet by Ampex's own duplicating operations in the 1960's into the 1970's (I think they stopped making mass-duped reel tapes in the 70's sometime but I don't know exact details). I would say that maybe half or more of _all_ the duped quarter-track tapes ever made under contract from various record labels were made by Ampex and used Ampex 600. Indeed, bottom line, there might be more Ampex 600 series tape more widely spread around the world than any other tape type, and perhaps more feet of this type were sold than any other type although that might be wrong because mass-duped tapes barely caught on as what one could call a mass medium.

My point is, if this tape were head-destroying and unstable, I think we'd have all sorts of anecdotal evidence. Tape collectors seem to be a chatty bunch and there are several message boards where they congregate. Plus, based on how much government surplace Ampex 641 and 631 tape I've seen on eBay, there must be a decent number of these tapes in various government archives and collections. I've seen no postings about 600 tape leaching something that ruins heads, nor have I ever heard this story about any brown-oxide/no-backcoat, of any type from any manufacturer, before. Meanwhile, you see these Ampex-duped quarter-track tapes in second-hand stores and all over eBay and I'm sure some members of this list have large collections. Has anyone on this list seen any evidence that Ampex 600 type tapes are destroying their tape heads?

Just to be clear, I don't have a dog in the fight except that I have owned and transferred many dozens if not hundreds of Ampex 600 type tapes and they don't seem to wear out any of my tape heads any worse than any other types, perhaps less so because they are somewhat highly polished and have thin oxide layers compared to earlier brown-oxide types.

-- Tom Fine

----- Original Message ----- From: "Charles A. Richardson" <charlesarichardson@xxxxxxxxxxx>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Tuesday, April 08, 2008 1:59 PM
Subject: 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.


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.

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