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At 01:02 PM 4/3/2006, [log in to unmask] wrote: >Richard: > >This is an increasingly common problem with a number of video tapes as well. >If, in past postings, you have seen me mention "binder-base adhesion >failure"- this is what we have been calling the phenomena for the last few >decades. >... >Final comment- we developed a procedure to deal with binder-base adhesion >failure about 10 or 15 years ago. Unfortunately, the procedure takes a few >months and is only successful about 60% of the time. > >With the work in tape restoration and recovery we have done over the last 23 >years, we consider binder-base adhesion failure to be a much more serious, >though less frequent, decay problem than binder hydrolysis. Well, this is the first major instance of BBAF that I have seen, but the Cal State Fullerton tapes were showing an incipient version of that and we did trace that to a nightly economizer cycle in the HVAC system. We also found this to be a self-healing situation as I've previously discussed. The conditions were precisely as you describe with daily variations in relative humidity ranging up to 75% overnight on some days. In your treatment of BBAF is there any risk that the currently stable portion of a tape showing partial BBAF might have the now-stable portion made worse during the treatment? That was a discussion we had and we opted to look for the stable sections as the opening was stable and we felt there was a chance that it was stable farther on. We got 10 of approximately 13-15 minutes of total family voices recording on the tape. The clients were pleased. When we unspooled the BBAF sections, many of the portions came off like a badly started roll of toilet paper with two separate layers coming right off the spool. Thanks, Richard Tape Restoration Seminar: MAY 9-12, 2006; details at Web site. 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