Started Longerons

I started working on the longerons tonight.  First up is to cut them to length.  This is a critical cut because replacing these 15' long angles would be very expensive (both in material cost and in shipping).  These need to be cut to precisely 173 7/16".  Since the ends of tape measures can have some slop in them, a trick to get more precise measurements is to position the tape measure at the 1" mark.  You do have to be sure to add 1" to your measurement to account for this though.



These suckers are long.  They barely fit across my garage widthwise because of the stuff I have lining both walls.



I used my cutoff saw to cut these about 1/8" long and then filed them to the correct length.



The aft ends of the longerons need some material removed.  I misread the plans at first that called for a 1/8" radius and drilled a 1/8" hole (1/16" radius).  I fortunately had drilled the hole far enough away from the lines that I could file the radius to be 1/8" and still not cross the lines (though it doesn't look like it from this picture).



Here are both ends cut and polished.



Next up is to lay out for the bends.  These lines define the forward end of the F-721 side rails and the point at which the longerons bend downward to meet up with the firewall.



The longerons are straight for the next 10+ inches or so, then curve inward to define the shape of the fuselage.



I placed marks every inch or so to help with the alignment during bending.



This is the rear end of the curve.  The longerons are straight from this point back to the tail.  It's nearly midnight, so I'll get started on the bending tomorrow.