Mike,
Yes I did first I put down a piece of neoprene, the a flat board and then I used a 15 lbs weight.
However I don't know if it did much. The glue I used was Titebond Thick and Quick, also known as Molding and Trim, and it sets up three time faster than Original. So by the time I got all the way around a row the first segment you could not move at all. I still used the weight. I let them setup about half an hour and then went back to it and started another row. Titebond Thick and Quick dries clear and you can hardly see it, no color like original or Titebond II or III.
One thing that is absolutely critical with these open segments is having your rings absolutely flat. You have to flatten every row. I tried cheating on one row and paid the price. It takes so very little to make a segment piece go wonky. When you think you have the ring flat check it again, it is time well spent.