David Riley:

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Chuck's advice was to do what he did: make a plywood box, put a 25W bulb in, and "bake" it in there for a few days (sans vinyl jacket). That won't get you above warping temperature. Please don't bake any plastic-based media at 300F.

Did Chuck say why to do this, what this baking would accomplish? The previously referenced Web page which discusses baking audio tapes says: "The purpose of "baking", is to drive out all the moisture that the tape binder has accumulated, which is what caused it to go sticky in the first place." I do not know that this applies to diskettes and the binders used on their surface coatings. another Web page on baking tapes is: http://www.wendycarlos.com/bake%20a%20tape/baketape.html ..and one Google search hit for "guzis bake diskettes" says, Chuck baked *10-inch tape reels", not diskettes; and the thread was about baking TK50 tape cartridges. Read the thread. https://www.mail-archive.com/cctalk@classiccmp.org/msg04318.html [Re: TK50/TK70 Info, Chuck Guzis Fri, 28 Aug 2015] another "hit" is on the mark: here's an exerpt. http://marc.info/?l=classiccmp&m=137627575108631&w=2 [classiccmp list Re: MFM floppy disk write precompensation Chuck Guzis, 2013-08-12 2:18:15] Sure, remove the cookies from the jackets, bake them at 140F for 4 or 5 hours, then apply a good-quality synthetic auto paint sealant--Klassic seems to be pretty good. No abrasive polishes, please..... That seems to provide a slick enough surface to keep the heads from grabbing the oxide--at least for a few reads. The alternative is disaster....Basically, you want to prevent the heads from "grabbing" the oxide. Once that starts, you're looking at a circle that you can see through. Get yourself an old box of Wabash floppies (any size) and play around......[end excerpt] --------------- Kyle Owen, good student he is, did his homework, and corrected my assumption that the Mylar would buckle - it's much more temperature tolerant, which you'd want for a stable magnetic backing. Thanks, Kyle! In any event, I did an uncontrolled experiment. Briefly: several minutes of baking an 8" diskette envelope (probably PVC?) and the diskette media cookie (Mylar coated with oxide) at 110-120 degrees F, did not seem to immediately distort (melt) either cookie or envelope. But minutes into a 180 degree spike, turned the envelope to a waffle, and put noticeable distortion into the cookie. When cooled, the cookie showed some distortion - I could not say it was sufficient to cause read errors. Of course the envelope was trashed. Again - I'm not convinced baking floppy diskettes, will solve any problems with mold or "moisture", which occurs more often than "flaky" diskettes. Chuck Guzis - who has informed me many times through the decades on matters floppy - seems to use this method to re-bind magnetic coatings on diskettes. and that's consistent with the same method, used to re-bind magnetic coatings on a certain class of 1970's audio tapes, some old DEC magnetic tapes, etc. This was informative discussion, thanks! Herb Johnson -- Herbert R. Johnson, New Jersey USA http://www.retrotechnology.com OR .net