I thought Sticky shed was visible... (still learning here, as I too have had this problem).

- hugh paterson 


On Feb 20, 2013, at 11:17 AM, Michael Biel wrote:

> The fact that the decks have stopped themselves on some of these makes
> it OBVIOUS that these tapes suffer from  Sticky Shed Syndrome.  If you
> continue to play these tapes while they squeal you will probably
> mechanically record the squeal onto the tape due to the actual movement
> of the oxide particles on the tape.
> 
> And by the way, you are another of those on the list who have set your
> email program to have our replies sent to only you instead of the list. 
> Please change this.  
> 
> Mike Biel  [log in to unmask]  
> 
> 
> -------- Original Message --------
> Subject: [ARSCLIST] Squealing Audio Cassette Tapes
> From: Karl Fitzke <[log in to unmask]>
> Date: Wed, February 20, 2013 1:20 pm
> To: [log in to unmask]
> 
> Greetings, and thanks right away for your interest and potential help 
> with the following:
> 
> We have a set of approximately 30 SKC Brand, GX and LX model, Type I 
> cassette tapes on hand to transfer. They are 60 minute tapes.
> 
> The original field recordist is from New Zealand, where these tapes were
> 
> recorded.
> 
> A number of the tapes start squealing after five to twenty minutes of 
> play, and this happens on at least three different Nak CR-7A machines 
> (dual capstan).
> 
> The squeal is a rather constant tone in amplitude and frequency (2 kHz 
> or so is a guess). The decks have even stopped themselves in some 
> instances. The squealing in some instances has stopped when I stopped 
> the deck, remove the cassette from it for inspection, replaced, and 
> played again. But, only to likely start again a little later.
> 
> Tapes have been fast forwarded and rewound before being played. I 
> believe the squealing has happened when the tape is packed even better, 
> e.g. after a play on one side (which didn't have noticeable issues). 
> But play of the first side may not have been monitored very closely by 
> personnel, so don't give that all too much weight.
> 
> I've occasionally seen conical wrapping at the outside of the pack (the 
> outside 1/8" or so, thinking radially).
> 
> I've transferred some of these tapes to new Maxell shells, removed 
> friction sheets in the original shells, removed pressure pads in the 
> original shells, loosened case screws in both shells, threaded tape on 
> the inside (instead of outside) of the posts near the cassette shell 
> rollers in the Maxell shell.
> 
> I checked W/F specs on all machines. They are okay, or just out of 
> spec, which does not concern me here (yet).
> 
> The best I've done is maybe reduced the amplitude and regularity of the 
> squealing with playback of one tape I recall, but I haven't gotten rid 
> of it.
> 
> My current belief is that we have lubricant issues, and I'm off to 
> read/reread everything I can find in old emails from Richard Hess, Marie
> 
> O'Connell, Steve Smolian that I saved for future reference, like the 
> ones I've forwarded below.
> 
> I'd be happy to hear anything else someone may have to offer. Even moral
> 
> support! ;-D Thanks again for your interest.
> 
> Best wishes,
> Karl F.
> 
> -- 
> 
> Karl Fitzke
> Audio Engineer
> Macaulay Library
> Cornell Lab of Ornithology
> 159 Sapsucker Woods Road
> Ithaca, NY 14850
> 
> 607-254-1100
> 
> [log in to unmask]
> 
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