Tom has decided to make these fins available as a product from his UP Truck Center business. He is offering fins to fit 1/2 inch and 5/8 inch tubing in lengths from 24 inches to 34 inches. He also offers a sort of super fin option that achieves more wrap of the fin around the tube. The prices are very reasonable, and I think this is a good option for anyone wanting to save some time on building the fins.
Here is the web page describing all the options and some notes on how best to install the fins...
Tom is a long time friend of Build-It-Solar, and has sent in detailed descriptions of some of his very well done solar projects... Thanks Tom!
Gary