Brief Description: Floor Stiffeners - Drill 601 angle, Part 1.
Floor stiffeners. I didn’t drill these at all like the plans call it out. I didn’t do it at all like the logs I visit either. I wanted to avoid using the angle drill. I also wanted to secure the ends of both inner and outer stiffeners before putting on the bottom skin and drilling the stiffener flange through the skin.
I dealt with forward end of the inner stiffeners first. Oh, be careful, these stiffeners have a front and back end. The joggle is bigger on the forward end.
The first thing I did was to mark the 601J Angle of the firewall for the 3 holes and then drilled them. This is the last thing the plans have you do.
I also used my new procedure of back drilling through a 1/8” aluminum bar to get the holes exactly where I want them. It works. None of this drilling them first with a smaller #40 and chasing the cross and hope for the best. I clamped the bar directly over the x and drilled away. You can see in image 2 I rotated the drill bit in the hole and you can see the mark directly in the center of the x. I like this procedure, no hoping you get it right. It just works and it’s fast.
