Step 2 : bending the shallow cruve on the longeron around the aft canopy deck part F-721B
In this step, I am making the bend along the af canopy deck that starts from 38" 7/16 and 69" 9/32 according to the markings we have made earlier.
I will be using the bending dies purchased from Buller Enterprises.
I marked the spar with a vertical line at every inch. These will be used to center the spar in the dies.
( update : 1 inch is a bit too narrow actually. If you use 2 or even 3 inch, it works as good and you will get less marking on the longerons. I only found out doing the second one.)
Then center the longeron with the marking on the die and make sure the die blocks are aligned.
Put the dies in a vise and start turning. Don't close the dies completely ! The dies allow for over bending and spring back correction.
So only close the gap between the dies half way through.
I make a reference to that because I actually overbent it quite a bit on mine and had to push back. It's always better if you can avoid this.
Bend a little at a time and compare often to the template on DWG-11. I attached DWG 11 to a cardboard.
The longeron should be with 1/16" from the template and lay flat on the surface withing 1/16".
I'm close, but it needs some more fine tuning.
Anal as I'm being about this, I'll continue bending in the next sessions to try to get it as close as possible.
