[Description of how the solar tracker works]
[General design guidelines]
[alternatives to R22 freon for a thermal weight transfer fluid]

My DIY tracker is designed to hold three Canadian Solar CS6P-230 panels in portrait orientation of four panels in landscape (2 x 2) orientation. Currently it holds three panels but I wanted the option to add another panel in the future if I needed it.

Here you can see me using my trusty Solar Powered bandsaw to cut the tubing that will form the top and bottom of the frame. The easiest way to cut two piece of steel to exactly the same length is to line them up and cut them at the same time.

Using the same method to cut the angle iron that will be the ends of the frame.

Reinforcing the center of the frame where the bearings, shocks, and counterweight attach

make sure the frame is level and square before welding it together.
Here is the frame laid out ready to weld and I'm checking to make sure it's square.
The completed frame waiting for the paint to dry.
Main axle welded and ready to paint.
Initial test to see how much freon I'll need to get adequate stability and reasonably fast wake up. Initially I estimated I'd need 10 lbs, but figured I'd go with 15 lbs to increase stability and to help overcome stiff shocks in the winter time. However, the freon appears to move from one side to the other at about the same speed regardless of how much is in the there. The extra 5 lbs of freon slows down the wake up. I played around with the system for a couple months, adding and removing freon and changing the counter balance weight, until I ended up back at 10 lbs providing the best wakeup speed with good stability.