My plans call for a 10"x43" telescope tube. For the time being I have chosen to use aluminum irrigation piping available from a compnay in Nebraska. Hastings Pipe Company has developed a great reputation among the ATM community for the service they are providing to us. This tube was ordered with each end rolled to increase strength. The wall thickness is 0.064". Here it is pictured next to my disassembled Atlas EQ-G for scale.

A long-term goal for this astrograph to have a custom carbon fiber tube. This material provides superior strength and substantail weight savings compared with aluminum. The kicker though is a much lower coefficient of thermal expansion. Focus shift over prolonged imaging sessions is far less of an issue with carbon fiber telescope tubing.