I suggest to him he keep his listing but edit it and remove; (a) the reference to the John Long P1 as I have more than one un assembled J. Long kit and Longs crispy is very light gauge stamped aluminum sheet that is nothing like his vinyl, (b) all references to Vintage-Mylar as the product is neither Mylar nor Vintage. I agree that the rest of the listing is simply misleading and includes that "out" clause at the end. I agree, let him sell the stuff, just in an honest way, no fairy tales about rainbows or John Long. For those on the forum who know John Long, he is not happy when his name is misused like this.
Before a picture and some burn talk; Ron Shanko emailed me and will be visiting with "the collector" and putting a multimeter on his crispy to determine if it is either metal or Mylar/other-plastic. This means we all get an answer to part one of the crispy mystery soon. Yeah for us.
The Tooling Question: Carbide is a modern material that is better than tool-steel or hardened-steel rollers/dies as it last longer. J. Long's stuff looks as crispy as mine yet I'll go out-on-a-limb and bet his supplier used regular tool steel. The type and source of the TOS-original and J.Long materials are still not known, but Ron Shanko agreed the multimeter test on a real Midgrade was pretty innovative idea and he is both excited about it and, ready to do it.
Burning: Look up Jon-Paul Lussier on the Boston Architectural College website. He is listed as Faculty. An award is set up in his name. I'm retired at 44 years young. That guy is me, not my Dad. I'm not old, just a PIA sometimes. I need facts, sources to back them up, and keep asking "Why" maybe too much. Retirement did not do that. This is just my nature.
The Burn Test Basics; Natural fibers burn up and leave ash behind. For example real silk smells like burning hair, real linen and cotton burn fast and leave only ash. Wool self extinguishes. Manmade silk (aka Rayon) produces thick black acrid smoke and blobs-up sometimes producing dripping molten flame-drops. When one takes a class in finish materials, that includes; fabrics, floor covering, and wall covering, one learns all about these traits via lab experiments and real life examples. All this relates to Life Safety and varied federal regulations.
Man-made stuff is petroleum based and usually burns as such. By removing some backing material and smelling the smoke it was very easy to identify the backing as hemp (the stuff old school rope is made of). And the silver cover as vinyl. Here is how...
I bought 20 samples of the "alleged Mylar" and sealed it in a polypropylene bag for a few days. When I took a sniff of the bag there were two odors; (a) hemp musk, (b) plasticizer. Plasticizer are used in PVC vinyls to impart flexibility. Think of a new car smell, that is plasticizer. When PVC based vinyls burn they drip and produce lots of black smoke wisps that float off into the room. The alleged crispy vintage Mylar did this. It was for sure vinyl.
Mylar (Metallized Polyethylene Terephthalate); burns slowly after the flame is removed, produces nearly no-smoke and smells pleasant like a candle, and leaves a paraffin wax like residue behind BUT MOST IMPORTANT does not stretch into fine filaments. This is unique quality of Mylar (MPET).
Vinyl on the other hand; produces sooty smoke, continues to burn rapidly after a flame is removed, will have a black bead on the burnt end AND MOST IMPORTANTLY will stretch into fine filaments, it also smells like burning asphalt or fishy-celery (yuk). A distinct nasty smell.
However there is a simpler non-burn test; Mylar (Metallized Polyethylene Terephthalate) does not stretch, PERIOD. Vinyl does (thanks to the plasticizer). Ever try to stretch a sheet of drafting mylar? You can not. The alleged Vintage Crispy Mylar does stretch in spite of having a backing fabric.
Mylar (Metallized Polyethylene Terephthalate) without the metal coating part is in fact the stuff we old designers once drafted on with plastic leads and ink.Why? It was "dimensionally stable" (no stretch) and we never had to worry the drawing would become "out-of-scale" because the sheet had stretched, or shrunk for that matter.
To answer what you call "THE BIG QUESTION" I submit that all you need do is contact me and I will mail you a no-cost real "stamped aluminum sheet extra crispy" that is identical in appearance to John Long's extra crispy EXCEPT it will not fit a John Long P1. John's P1 shells require a uniquely longer and wider crispy that can only be obtained from him. I just dared ya...LOL. I love doing that. Now for extra crispy's up-close and a peek at the enigmatic real Midgrades owned by a ghost. Photo's used with Owners permission.