Having dealt with squealing tapes at virtually all recorded speeds and (most)
widths, the simplest and most effective solution I’ve found is to lubricate
them. That said, the most effective lubricant I’ve used so far is from Last
Factory. 
https://www.lastfactory.com/

I have used LAST Tape Preservative on Polyester and Acetate audio tape and
magnetic film for over 12 years now with roughly 95% success. Walt Davies at
LAST Factory was unsure about the use if their products on acetate but I tried
it anyhow and have had no adverse results.

If someone has experience with a solution that is equal or better, I’d love to
hear about it because it can get expensive treating the 35mm elements for an
entire feature length film.

Playing tapes at higher than the originally recorded speed can cause some
unwanted results:
1) Unless you have modified your play electronics, playing, for example, a
7.5ips tape at 15ips will invoke a different EQ alignment curve which will
result in inaccuracies when pitching the file back down in the digital domain.
(Something I don't like to do in the first place for a number of reasons)

2) Having tried this and observed the signal with calibrated test equipment
showed that the squeal is, more often than not, still there and although it may
not be (as) audible, it is having an effect on the audio in other ways such as
increased harmonic distortion, induced wow and flutter, etc.

Cheers!

Corey Bailey
Corey Bailey Audio Engineering	


Quoting "Richard L. Hess" <[log in to unmask]>:

> Hi, Marie,
> 
> I would love to see photos of your latest as well.
> 
> Shai jumped a beat. Unwinding tapes that stick together is done 
> slowly, but playing tapes that squeal at a faster speed will 
> sometimes change the dynamics of the mechanical system enough to 
> avoid the squeal--or at least move it up to a point where it no 
> longer is in the audible frequencies (further analysis needed). On 
> the other hand, a different tape path is also sometimes a solution. 
> The Racal instrumentation (IRIG) machines seem to do that well,  but 
> post-eq is required in the DAW. I wrote about fast playback of tapes here:
> 
>
http://richardhess.com/notes/2007/11/08/success-with-squealing-shamrock-031-tape/
> 
> related info on the Racal here:
> http://richardhess.com/notes/2007/11/21/how-to-play-4-track-1875-ins-tapes/
> and
>
http://richardhess.com/notes/2008/01/09/using-the-proper-toolsand-dont-try-this-at-home/
> and
>
http://richardhess.com/notes/2008/04/15/a-solution-to-reduce-spoking-in-old-acetate-tapes/
> 
> Cheers,
> 
> Richard
> 
> At 04:14 AM 2009-12-16, Marie O'Connell wrote:
> >I don't think Richard meant fast, infact, slow.....lllllllll.......yyyyyy
> is
> >very helpful.  We have modified 2 of our Studer B67 to be low friction
> >machines and that has helped alot.  I can send pics when I get back to work
> >in the morning.  I rarely use the isopropyl drip machine now because of
> >these 2 .  They do a grand job.
> >
> >Cheers
> >Marie
> >
> >On Wed, Dec 16, 2009 at 8:17 PM, Shai Drori <[log in to unmask]> wrote:
> >
> > > It's sad to hear Peter passed away. His knowledge was extensive and his
> > > humor was in the best British tradition. I wonder if I have a 
> > picture of the
> > > thing somewhere. BTW, I didn't think about playing squealing tapes fast,
> > > that's a good idea, Thanks Richard. I'll try it next time a tape comes
> in
> > > that does that. I didn't think about it before but I now realize that
> all
> > > the tapes that squealed  were 3.75ips.
> > > Shai
> > >
> > >
> > > Mark Campbell wrote:
> > >
> > >> Please tell us more about the "grandfather clock" tape recovery
> machine.
> > >>
> > >> Mark
> > >> -----Original Message-----
> > >> From: Association for Recorded Sound Discussion List
> > >> [mailto:[log in to unmask]] On Behalf Of Shai Drori
> > >> Sent: Wednesday, 16 December 2009 8:12 AM
> > >> To: [log in to unmask]
> > >> Subject: Re: [ARSCLIST] Tape Shed-Sticking & stripping
> > >>
> > >> This reminds me of the "grandfather clock" thingamajig I saw at the
> > >> British library. It is a large board with rollers that the tape goes
> > >> through making a serpentine. The tape travels very slowly and can be
> > >> heated or chilled as needed. They made this for some agfa tapes that
> > >> stuck. I have never had a 3m 176 make trouble but this sounds like many
> > >> 50's 60's tapes I transfered that were of American origin. One squealed
> > >> so bad we had to soak it with silicone. I am wondering it there is a
> > >> benefit to slow winding under a cold air blast, like an air
> conditioning
> > >> duct pointing at the transport. My a/c/ has a setting for drying the
> > >> air. Very cold air forced out and the rh drops very fast..
> > >> Shai
> > >>
> > >> Richard L. Hess wrote:
> > >>
> > >>
> > >>> Hi, Martin,
> > >>>
> > >>> This is very problematic, and I do NOT think baking is a good idea.
> > >>>
> > >>> There is a CHANCE that month-long cold soak in a desiccated atmosphere
> > >>>
> > >>>
> > >>
> > >>
> > >>
> > >>> (silica gel inside double freezer (or foil) Zip-Loc bags in the fridge
> > >>>
> > >>>
> > >>
> > >>
> > >>
> > >>> (not freezer)).
> > >>>
> > >>> It has worked for some 3M 176 that showed this symptom. It has also
> not
> > >>> worked for other tapes. Jim Wheeler gave me this technique. I 
> > don't know his
> > >>> source. I haven't used it much.
> > >>>
> > >>> The other thing to try is VERY slow unwinding - 1.88 in/s or slower.
> > >>> Sometimes that alone helps.
> > >>>
> > >>> The tape in the photo was baked based on a consensus of the people at
> the
> > >>> seminar (including the tape owner) because we didn't have time for
> > >>>
> > >>>
> > >>
> > >>
> > >>
> > >>> cold soak and we wanted to see what would work (or not).
> > >>>
> > >>> Since that article, I have had good results with 3M201 which had the
> same
> > >>> problem and the 1.88 in/s wind-through solved it.
> > >>>
> > >>> Good luck!
> > >>>
> > >>> Cheers,
> > >>>
> > >>> Richard
> > >>>
> > >>> At 12:34 PM 2009-12-15, Martin Fisher wrote:
> > >>>
> > >>>
> > >>>> Got a polyester/plastic non-backcoated reel in which the binder is
> > >>>> stripping off onto the adjacent wind.  AKA "binder adhesion to 
> > back of next
> > >>>> layer" on Richard Hess' site.
> > >>>>
> > >>>> http://richardhess.com/notes/2006/05/26/binder-adhesion-to-back-of-ne
> > >>>> xt-layer/
> > >>>>
> > >>>>
> > >>>> Might baking be a solution for this?
> > >>>>
> > >>>> Martin
> > >>>>
> > >>>>
> > >>> Richard L. Hess                   email: [log in to unmask]
> > >>> Aurora, Ontario, Canada       (905) 713 6733     1-877-TAPE-FIX
> > >>> Detailed contact information:
> > >>> http://www.richardhess.com/tape/contact.htm
> > >>> Quality tape transfers -- even from hard-to-play tapes.
> > >>>
> > >>>
> > >>
> > >>
> > >>
> > >
> 
> Richard L. Hess                   email: [log in to unmask]
> Aurora, Ontario, Canada       (905) 713 6733     1-877-TAPE-FIX
> Detailed contact information: http://www.richardhess.com/tape/contact.htm
> Quality tape transfers -- even from hard-to-play tapes.  
>