I have been a power pipe nut for latest several years, always wanting to make a nice pipe for my old saws to let them work again in wood. So showing here is a very simple and easy pipe-make-helper for straight and corn pipes. What you need in the operation is some of your muscle labor to it, so I am afraid you will be disappointed if you expect very decent and precision work with this tool, lol.
For straight pipes;
Cut out a rectangle pipe;
Add L angle bars, and a couple of round bar, been cut in the same length;
Make a couple of spacers. Their sizes are up to the sizes of the pipes in your project, but should not be too large, like the one you use for air ventilation of a house.
Place the spacers at the both ends;
Widen one of the ends;
Buy a baseball bat, lol.
Give it a nice cut and shape it up!;
(will post how I use it later...)