The next phase was plumbing inside the collectors, which meant the fabrication of the heat absorbers. Using rolls of Aluminum flashing as the raw material, I cut and bent it into absorber plates to fit over the pex. I also cut thinner strips of the Aluminum for underneath the pex. The thinner strips acted to increasing the surface area of heat transfer into the pex and also provided a convenient guide for laying the drainback serpentine pattern as I went along.
AL roll, and marking cuts for top absorbers.
AL piece ready to be bent in my former device (scrap wood form, 5/8" steel bar and a big ol' mallet)
How it fits together.
Apply brute force!
You can see my construction processes; Starting with the back absorber strip as a guide, then straightening the pex over it. Next, applying plenty of Silicone caulk between the two absorber pieces as well as the pex. Everything was nailed onto the plywood with brads because heavy duty staples wouldn't go through the Aluminum.