This is a chin-up bar I made for my brother in law. Help helped of course.
First is one of the two triangles. Each one is made from a single piece of angle iron, with corners notched on only one joint where the outside edge was welded. Notice it has been drilled for bolts or lags to attach it to a wall.
This picture shows the two triangles with a round tube welded in each end to finish up the chinup bar. It is meant to bolt up to a wall with 16" between studs, skipping two in the middle. In other words, it is desgined to bolt to wall studs 48" apart. Last I knew he was using in and it was very nice, and very sturdy mount to his wall.
Here is the final picture of it hanging on a wall in his garage.