Carton 100mm f/13 "MD" OTA Construction - Main Tube (Cutting to proper size - Step 3 of 5)
 

The main tube successfully cut to size with a hacksaw. (Click to see an enlarged image.)

 
Here is the end result of using the card stock wraparound method to cut my main tube to the proper length of 39.875". It produced a near perfect perpendicularly cut around its circumference. So if you do not own one of those really nice chop saws, this inexpensive method can generate similar results. All you need is good a quality hacksaw, a sheet of thick paper, or better yet card stock, some elbow grease and a good amount of patience; and you are good to go.