More fitting the firewall and fitting floor stiffners - 4 hours

I started off by removing the firewall and moving the centerline on the F-601M-1 angle/stiffener aft by about 1/32". This allows the forward face of the firewall to sit exactly 5/8" aft of the side and bottom skin edge.



I refit the firewall to the fuselage and then carefully drilled the outermost holes and clecoed them.

I now checked the required 5/8" distance along the sides and towards the op of the firewall and it looks like I am going to do some work to get things sitting correct. The sides of the firewall are bowed a slight bit and is not sitting well/in-line with the side skins. I  will have to remove the firewall and "massage the side flanges" to get a better fit. I also see that I have to trim just a small amount of longeron to get the proper 5/8" distances.

I'm putting that on the side for now, and I opted to check how the floor stiffeners fit. I first marked edge distances on all sides of the angles so I can easily identify trouble spots.


I then used the edge distances to help forward/aft placement of the angles


I was able to see how the angles interfere at the firewall. I could then easily mark and trim the floor stiffener to fit around the firewall angles.


An excellent fit!