This is the latest design. We needed something that would be able to withstand the large number of cycles so we decided to add another piece of PVC to the old design. The testing is currently going. We are applying about 300-350 pounds and have ran about 60,000 cycles.
We are still using the bolt to hold things together and it seems to be giving us the support that we need. The bolt is holding things together well. We didn't add any stress relieves in this one because of some of the research that was done by a capstone group a year or two ago. They said that with PVC, there really is no need for stress relievers.
I went in with my family today. My little son Brogan is looking on to see what his dad is up to. He is such a curious little guy and always wants to be in the mix of things.