Found this photo in my original Rig photos. This is that tube:
Bullfrog makes a good point about learning lost skills. Anyone wanting to see some of the stuff young people in the earlier 20th century learned from could visit this "Chest of Books" link. This is set to Crafts but there are so many other vintage things to see in that archive site. Lindsay Technical Books used to advertise in Popular Mechanics magazine but went out of business. "Your Old Time Bookstore" YOTB, sells many reprints today.
Of course some of the things being used from auto scrap yards in that time may not be available today. MAKE & Instructables carries on the tradition only using more modern materials now.
Chest of Books/Crafts
Chest of Books main site
Lindsay Technical Books (out of business) are available at YOTBS