Re: [ARSCLIST] Can Magnetic Tape Be Frozen?

["Watsky, Lance" <lwatsky@xxxxxxxxxxxxxxx>]

Just wanted to take a moment to thank everyone that responded to my posting.  

Lance Watsky
Preservation & Media Specialist
The Georgia Archives
5800 Jonesboro Road
Morrow, GA 30260
678-364-3764 (phone)
678-364-3860 (fax)
lwatsky@xxxxxxxxxxxxxxx
www.GeorgiaArchives.org




-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:ARSCLIST@xxxxxxx]On Behalf Of Peter@xxxxxxxxxxxxx
Sent: Wednesday, December 01, 2004 3:06 PM
To: ARSCLIST@xxxxxxxxxxxx
Subject: Re: [ARSCLIST] Can Magnetic Tape Be Frozen?


Fatty-acid lubricants will crystallize at very low temperatures (I have
pictures of the crystals).  On the other hand, every tape I have seen with
crystallized lubricant reabsorbed the lubricant after a few days of exposure
to "room" temperature and played without friction problems.

I won't make any formal recommendation but, if I was faced with the choice
between acetate breakdown and lubricant crystallization, I would risk
lubricant crystallization every time.

Another issue that should be looked into (and I have seen no data on) is the
difference in the thermal expansion/contraction factors between a polyester
recording layer and an acetate base layer.  If the thermal
expansion/contraction factors are sufficiently different, freezing could
promote binder-base adhesion failure.  Unlike binder hydrolysis that can be
easily treated, binder-base adhesion failure is often considered
catastrophic and unrecoverable media failure.

Peter Brothers
President
SPECS BROS., LLC
(201) 440-6589
www.specsbros.com

Restoration and Disaster Recovery Service Since 1983

> -----Original Message-----
> From: Association for Recorded Sound Discussion List
> [mailto:ARSCLIST@xxxxxxx]On Behalf Of Rick Taylor
> Sent: Wednesday, December 01, 2004 1:12 PM
> To: ARSCLIST@xxxxxxxxxxxx
> Subject: Re: [ARSCLIST] Can Magnetic Tape Be Frozen?
>
>
> Hi Lance,
>
> The Image Permanence Institute Media Storage Quick Reference
> (http://www.climatenotebook.org/MSQR/MSQR_home.html) says:
>
> [Acetate tape:] COLD [i.e. 40 degrees] is recommended because
> risk of lubricant
> separation is considered to be less likely than acetate base
> degradation. If
> the A-D Strip reading is 2 or greater, tape should be stored at the FROZEN
> condition and copied as soon as possible.
>
> [Polyester tape:]  COOL [54 degrees] is consistent with ISO
> recommendation for
> 50% max. RH. COLD may cause lubricant separation with some tape
> formulations.
>
>
> Rick Taylor
> Graduate Student
> Kilgarlin Center for the Preservation of the Cultural Record
> School of Information
> University of Texas at Austin
> rtaylor@xxxxxxxxxxxxxxxxxx
>
>
> Quoting "Watsky, Lance" <lwatsky@xxxxxxxxxxxxxxx>:
>
> > This is being posted for Beth Delaney, Nederlands Institute for
> Sound and
> > Vision
> >
> > "Can anyone tell me if it is acceptable to freeze magnetic
> sound film?  I
> > don't seem to find in any literature that this is not a good
> idea. Often the
> > literature states that it is recommended to "freeze acetate film", not
> > differentiating between acetate image material and acetate
> magnetic sound
> > film."
> >
> > I personally believe that it is probably not recommended, but I
> wanted to
> > check with the ARSC folks, before responding back to Beth.
> >
> > Thanks,
> > Lance Watsky
> > Preservation & Media Specialist
> > The Georgia Archives
> > 5800 Jonesboro Road
> > Morrow, GA 30260
> > 678-364-3764 (phone)
> > 678-364-3860 (fax)
> > lwatsky@xxxxxxxxxxxxxxx
> > www.GeorgiaArchives.org
> >
> >
> >
> >
> > -----Original Message-----
> > From: Association for Recorded Sound Discussion List
> > [mailto:ARSCLIST@xxxxxxx]On Behalf Of Jack Raymond
> > Sent: Wednesday, December 01, 2004 9:14 AM
> > To: ARSCLIST@xxxxxxxxxxxx
> > Subject: Re: [ARSCLIST] LP Groove Repair
> >
> >
> > Eric Jacobs wrote:
> >
> >  > I have a 1963 LP which has a deep gouge - it looks like the
> needle had
> > been
> >  > dropped very hard, leaving a pit in the record that is 2.5
> grooves wide.
> >  > Depending on how I set the anti-skate, I get one of two
> effects: (a) the
> >  > stylus skips and will not continue past the gouge or (b) the
> stylus jumps
> > a
> >  > groove, skipping 1.8 seconds of music.  I've looked at the
> groove under a
> >  > 150x microscope, and it appears that the gouge is 0.010"
> deep.  For the
> >  > really curious, I might try to photograph the damage.
> >  >
> >  > Does anyone have any experience on how to span this gouge?  Any
> > conservation
> >  > techniques for filling such damage just so to make the rest of the
> > grooves
> >  > playable?  Or am I just outta luck on this one.  I have a
> steady hand and
> >  > good optics/magnification.
> >
> >
> > Here is a method that works well for repairing digs on 78s, and
> you might try
> > it
> > on your LP:  Place the record under a strong light.  Squeeze a drop of
> > Elmer's
> > Glue-All onto a piece of cardboard.  Dip the point of a needle
> into the glue
> > to
> > pick up a tiny bead of glue and -- using a magnifying glass --
> transfer the
> > glue
> > to the pit in the record.  Repeat until the pit is filled.  Let it dry.
> > Apply
> > more glue if necessary.  Then, when completely dry, carefully
> shave the glue
> > flat with a razor blade.  Play the record with a light stylus
> and with no
> > anti-skate pressure.  The stylus will etch a new groove, after
> which stylus
> > pressure can be returned to normal.  The nice thing about this
> method is that
> > it
> > is reversible:  the glue does not bond tightly to the surface and can be
> > removed
> > easily.
> >
> > -- Jack Raymond
> >
>
>