The angle plate construction was based on the cylindrical parallels prepared on September 19, 2011. One side of a 3" X 2" X 2" X 3/8" angle iron was set against a cylindrical parallel with the other side up and parallel to the milling table. Two clamps were used as well as a machinist's jack to hold the work solidly.
Two through holes were drilled with a #11 drill bit for 10-32 screws after first drilling with a #27 drill bit. These were centered 1.5" apart. The angle iron was then removed and mounted against two cylindrical parallels and screwed to a bar on the back side of the parallels. It was also raised on a 3/8" support in order to sit above the parallels. Faced with a fly cutter taking off only 0.002" per pass on slow speed to provide a nice finish.
The drilling operation was repeated on the newly cleaned up face, so the first face could be set up similarly for fly cutting. An end mill was used to clean up all of the edges. For this a vise was used with a paper card used between the rough side and the vise jaw. Finally, the corners were beveled with a file.