Mark, you are a savior. I was just trying to figure out how to make use of the stack of barbell weights in the basement. I had gotten part of the way there by finding the steel set screw collars on the Home Depot site. Then I thought "I bet someone on Cloudy Nights has already gone down this path," and voila! This is a really elegant solution that just saved me lord knows how much to order a silly 5 pound counterweight and have it shipped cross-country.
Thanks for sharing!!