Hi, Steve, The Ampex patent has in its claims both 50 and 54 °C. That was where the higher temperature came from. It is still well below the Tg of the base film. (67 - 81 °C) (https://en.wikipedia.org/wiki/Polyethylene_terephthalate) Ampex patent here: http://www.richardhess.net/restoration_notes/USP5236790.pdf On 1/28/2016 4:10 PM, Steve Greene wrote: > I used to bake 15" quad reels with a high degree of success at 120F for 24 > hours, with a long ramp down time of another 24 hours before handling it. > Knowing what I know now, I might go as high as 125F. 54C (130F) seems high > to me. > > Steve > > Steve Greene > Audiovisual Archivist > Nixon Presidential Library and Museum > National Archives and Records Administration > (301) 837-1772 > > On Wed, Jan 27, 2016 at 8:38 PM, Corey Bailey <[log in to unmask]> > wrote: > >> Hi David, >> >> My experience with baking 2" tapes comes from my experiences at Warner >> Bros. Studios, Burbank, CA. As Richard Hess said: "456 is the poster child >> for SSS" so, don't ask, just bake it.! Regarding the question of how long >> to bake is dependent on the size and type of oven, the number of tapes to >> be baked at one time and (obviously) the condition of the tapes themselves. >> The oven at WB is commercial grade, capable of baking 34, 10.5" reels at a >> time. I've baked as few as two reels on up to an oven full. For two reels >> of 2", the average baking time is 18 - 24 hours. I would suggest that you >> only bake as many tapes as you can process in a day so that the >> stabilization process is as fresh as possible. You mentioned leader breaks. >> Expect any splices to have to be replaced after baking. Not always the case >> but, build the labor cost into your budget. >> >> Cheers! >> >> Corey >> Corey Bailey Audio Engineering >> www.baileyzone.net >> >> On 1/27/2016 8:29 AM, David Crosthwait wrote: >> >>> Hello Tom and Richard, >>> >>> In my digging through a church archive yesterday with new clients, we >>> uncovered many reels of 24 track on 2" among other audio tapes. One tape of >>> interest I have with me, destined to a comrade here in town who is as >>> passionate about vintage audiotape recovery as we are with videotape, is a >>> 24 track on "Ampex Grand Master" 456 from 1988 in a cardboard box. It has >>> track assignments within. The tape has leader breaks. In a test of sorts, >>> we are going to link this up with a 1" C of the concert (same production, >>> same date) to create a new stereo mixed version. I've done this before so I >>> am familiar with the routine. The question to you two (and others) is: What >>> should we expect from a stickiness standpoint (if any) from 1988 vintage >>> "Grand Master" 456? >>> >>> The client has multiple reels of this concert so this is a test of sorts. >>> The 24 track will create a ProTools session for the mix down and new stereo >>> imaging (5.1?), to be done at the client's facility. I'm going to be >>> remastering the 1" C today to file (it too is in stereo albeit with weak >>> L-R imaging as viewed on the phase scope). It's a full orchestra with choir. >>> >>> >>> Thank you. >>> >>> Best Regards, >>> >>> David Crosthwait >>> DC Video >>> Transferring NTSC, PAL& SECAM Two Inch Quad and Helical Source Tapes >>> (and More)! >>> >>> http://www.dcvideo.com/what-we-do >>> [log in to unmask] >>> >>> www.dcvideo.com >>> >>> Follow DC Video on Facebook: https://www.facebook.com/dcvideo >>> Follow DC Video on YouTube: http://www.youtube.com/user/dcvideoonline >>> >>> >>> >> > -- Richard L. Hess email: [log in to unmask] Aurora, Ontario, Canada 647 479 2800 http://www.richardhess.com/tape/contact.htm Quality tape transfers -- even from hard-to-play tapes.