thank you for being so clear. there are a lot of other videos on the subject but they are very intentionally vague so that viewers can buy some of their instructional material...
I was looking Steve Sint up today and found out that he died in 2014. I can't believe it. :( The knowledge contained in his photography books is worth gold.
OK, I just tried to make one for the first time using this video. And I did run into some problems. First, it is easy to put these hinges when they are closed to the edge. But it is pain when you try to do so say 2-3 feet away form the edge. Forget trying in the middle. Second, you need big table or saw horses or something to prop up the two 4x8 sheets. Third definitely need another person to help you. If you don't put hinges in the middle it leaves gaps. What I found is that you can first put hinges closer to the edge, stand up the V-flat and then put hinges in the middle using another person to help as you slide gaffers tape through the slit between two 4x8 panels. After making one myself, I will definitely try another method where you put gaffers tape all along the long edge and then decide which method is easier to replicate.