DaleB
Well Known Member
Floor stiffeners too close together
If you install the F-772B floor stiffeners according to the plans, or if you do it by just clamping the ends of the stiffeners to F-783B and F-601J before match drilling them to the floor, you will very likely end up with them spaced 8" between the OUTER edges of the vertical flanges. This will cause you problems when you try to install the F-782C cabin center cover, which needs the INNER edges of the stiffener flanges to be 8" apart. That might not be a huge deal, since the center cover is thin sheet metal and you may be OK with a little bow across the top - or maybe you could put the flanges outside the stiffeners instead of inside. If you're installing fuel injection, though, the F-7115A cover is .063 thick, 8" wide and won't be coaxed in so easily. A quick web search tells me I'm not the first to encounter this.
I'm still debating how I'm going to address this. It would have been really nice to have known about it earlier so I could have just spaced those stiffeners out 1/16 on each side, even if it took shims on the ends.
If I had this to do over again, knowing what I know now... I'd have skipped the F-7115A cover from the FI boost pump kit entirely. I would have used F-782C as it was, made a .063 stiffener plate to rivet in place underneath the boost pump and filter, and made some mounting saddles for the pump and filter out of blocks of UHMW or Delrin or something. Live and learn.
If you install the F-772B floor stiffeners according to the plans, or if you do it by just clamping the ends of the stiffeners to F-783B and F-601J before match drilling them to the floor, you will very likely end up with them spaced 8" between the OUTER edges of the vertical flanges. This will cause you problems when you try to install the F-782C cabin center cover, which needs the INNER edges of the stiffener flanges to be 8" apart. That might not be a huge deal, since the center cover is thin sheet metal and you may be OK with a little bow across the top - or maybe you could put the flanges outside the stiffeners instead of inside. If you're installing fuel injection, though, the F-7115A cover is .063 thick, 8" wide and won't be coaxed in so easily. A quick web search tells me I'm not the first to encounter this.
I'm still debating how I'm going to address this. It would have been really nice to have known about it earlier so I could have just spaced those stiffeners out 1/16 on each side, even if it took shims on the ends.
If I had this to do over again, knowing what I know now... I'd have skipped the F-7115A cover from the FI boost pump kit entirely. I would have used F-782C as it was, made a .063 stiffener plate to rivet in place underneath the boost pump and filter, and made some mounting saddles for the pump and filter out of blocks of UHMW or Delrin or something. Live and learn.