So I messed up the two holes that attach the two central floor stiffeners to the F-704 bulkhead: I clecoed the bottom skin to the aft part of the F-704 only so the front part of the F-704 bulkhead was not positioned properly.
I upsized the holes to #30, which fully cleaned it.
Now the question is, what do I do next? These two holes are special in that I am supposed to countersink the F-776 central skin and the F-704 flange, dimple the F-772 bottom skin and leave the floor stiffener "flat".
However, with the AN426AD4 rivet, I am concerned that the thickness of the F-776 plus the F-704 won't be enough for it. Seems risky to me.
So, that leaves me the following options:
1. I can use "oops" NAS1097AD3 rivet. It's head is about the same as the AD3 rivet, so I can follow the original plan of dimpling the outer skin and countersinking the other skin and the flange.
2. I can dimple the both skins and the flange, then countersink the stiffener, hoping that somehow I will be able to fit it, contrary to what instructions say. The angle, however, doesn't have much thickness for the AD4-sized countersink either (but it is probably easier to fix the angle -- do a fabricated joggle, for example).
3. I can put a universal rivet there. Leave these joints alone, don't dimple nor countersink anything, just put a domed head. Will probably loose one or two knots of the cruise speed
I am leaning towards #1 or #3, with a slight preference towards #1. What do you think?
I upsized the holes to #30, which fully cleaned it.
Now the question is, what do I do next? These two holes are special in that I am supposed to countersink the F-776 central skin and the F-704 flange, dimple the F-772 bottom skin and leave the floor stiffener "flat".
However, with the AN426AD4 rivet, I am concerned that the thickness of the F-776 plus the F-704 won't be enough for it. Seems risky to me.
So, that leaves me the following options:
1. I can use "oops" NAS1097AD3 rivet. It's head is about the same as the AD3 rivet, so I can follow the original plan of dimpling the outer skin and countersinking the other skin and the flange.
2. I can dimple the both skins and the flange, then countersink the stiffener, hoping that somehow I will be able to fit it, contrary to what instructions say. The angle, however, doesn't have much thickness for the AD4-sized countersink either (but it is probably easier to fix the angle -- do a fabricated joggle, for example).
3. I can put a universal rivet there. Leave these joints alone, don't dimple nor countersink anything, just put a domed head. Will probably loose one or two knots of the cruise speed
I am leaning towards #1 or #3, with a slight preference towards #1. What do you think?
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