The construction of the acrobatic card gaff was one of the questions asked. Don took out a piece of dental dam and showed us how he makes the gaff. For me, it was one of those, oh 'why didn't I think of doing it that way' kind of things.
Yes this gaff is very hard to make. It will take some experimentation to learn how much tension to put on the dam (depends on the thickness of the dam). You just have to be patient to learn this. After trial and error gets the right result, MARK YOUR WORK SURFACE so you know how far you pulled it and know where you placed the tape to hold the dam down while the glue dries and also know the exact position of the card. After you know these things, you'll have a template to make the gaff correctly and consistently. Making gaffs requires a lot of patience-- and quality tools and materials (i.e. precision cut knives, roller, card press, premium grade rubber cement and thinner, etc.)
Unfortunately, I really can't explain other nuances on how it is done in this 'text only' medium. (I tried typing it out the steps and it made absolutely no sense). If only I could draw illustrations like you Richard or write clear explanations. Don was selling a videotape of him lecturing on making gaffs. The explanation may be on that videotape. I don't know.
I'm going to try this weekend to make an acrobatic card up using Don's tips. I'll let you know how it went.
BTW, I always knew dental dam to be the latex square from the trick where you make a coin appear to penetrate and fall into a cup. After doing an Internet search to find out where I could buy it (other than at a magic store premium), I was shocked to find out its common non-magic and non-dental uses. Oh boy, more than I ever wanted to know. YUCK! I guess I'll just buy this at the magic shop.