Resolution of fit issue with CF-SKN-004 - part 2

The part shows the establishment of rows of 4mm holes in a blank piece of 6061-T6, exactly matching the spar carrythough holes. The difficulty here is the inability to match drill the skin from the other side of the flange, owing to the U-shaped construction. Use of templates, and the original skin was essential. Photo essay.

Previously it was found that the rev 1 skin rear holes are about 1.0mm aft of the carrythough rear flange holes, the front skin holes are about 1.2mm forward of the carrythough flange holes - consistent with the 2.2mm total mismatch observed above.

So if I cleco the new skin to the Rev 1 skin by the aft row of carrythrough holes, the outer boundary of the rev 1 skin will be aft by about 1mm of the correct outline of the new skin. I will trim the new skin to this outline, allowing for this correction, for the next stage of this process.

I may extend the new skin edge aft by an additional 2mm or so because fitment will allow it and this will increase the rather small 4mm hole-edge distance.