Started the longerons at about noon today and tried a couple of different methods. The method I ended up with is very similar to the one described in in plans.
This past weekend I bought a couple of pieces of 3/4" angle from Lowes and decided I would play with these practice pieces cause I was hesitant to start using the real parts. Read on the forums that the angle was cheap if it had to be replaced, the shipping charges would be terrible. (The angles are about 8' long.)
Initially I tried to open the angle at the forward end of the angle to 95.4 degrees using the vise, a 2" piece of 3/4" black pipe and some scrap angle that I had already opened up to about 97 degrees. Measured the required (95.4 deg) angle using a protractor from Sear's as shown in the pictures. This worked on my practice piece but did not work on the real angle from Van's. The alloy must be a bit harder!! I resorted to banging on it with a hammer!!! It sure hurts me when I hit my plane!!! Initially tried a rubber mallet and then a 5# dead blow hammer. The angle did NOT budge. Resorted to using a 3# sledge but instead of hitting the longeron, placed a piece of scrap 3/4" angle over the longeron and banged on it. Used the anvil on the rear side of my vise after putting a couple of pieces of duct tape on the surface. As you can see from the pictures, the piece of scrap took a beating. It takes some good raps to get the angle to open. As long as you take it slow and measure every so often, the angle will open to 95.4 degrees.
Measured the required twist using a digital level that I had. Bent the angle back 2.7 degrees using a "METRIC CRESCENT WRENCH". (See Figure 3 on Page 23-02, the best I can figure, one side of the crescent wrench must be metric and the other side must be SAE). Hi!!!!! LOL!!!! The engineering folks at Van's must of had a hard day.
Then bent the longeron to the template using the canopy deck template. I did not use a heavy soft faced hammer but instead bent the angle using my hands. Had very good control. Ended up with a very good match to the left and right templates.
During the bend process you will find that you have to rebend the longeron in the vertical plane. Was easy to accomplish by rotating the longeron 90 degrees in the vise and sighting down the plane of the longeron, bending as necessary with my hands. (This deformation is to be expected as explained to me during a EAA Chapter meeting, this is similar to the fluting that is required on a rib after it is bent to shape.)
Checked all of my bends by clamping the top face of the left longeron to the top face of the right longeron using some small c-clamps. They matched very well.
Will recheck all the next day and then continue.
Time - 8 hours (includes my play time)
