Fitting rear-centre fuselage joining stringers and upsizing skin holes

Both left and right top joining stringers CF-STR-002 have 3.2mm holes which match the centre and rear fuselage side skins. These were rivetted first

The middle and bottom stringers CF-STR-001 3.2mm holes matched the front side skin holes, but mismatched the rear fuselage side skin holes by about 0.9mm as shown here. The bottom string was slightly worse. Situation was the same on both sides

These holes were recentred/upsized to 4.1mm and in the aftmost hole 4.8mm

When all the stringers were riveted, the vertical run of 4.1mm holes joining the skin could be clecoed, but nonetheless did not match perfectly. The mismatch was about 0.8mm on both sides, becoming slightly less towards the bottom.

Closeup of typical mismatch.

So these holes were all recentred/upsized to 4.8mm. The centre-edge distance varied from 8mm at the top, up to 10mm at the bottom

All the mismatch was cleared, with no detectable elongation in any of the layers, except in the top couple of holes.

At the bottom

Slight elongation in one or two holes in the corner skin