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Chapter 8: Can I take off the front spar caps to final-sized drill the doubler?

gotyoke

Well Known Member
Chapter 8, page 4, step 4 says "Step 4: Except for those indicated in Figure 1, final-drill #30 the 1/8 [3.2 mm] holes common to the HS-00902-1 Front Spar and the HS-00907-1 Front Spar Doubler."

It does not mention the HS-00913 spar caps, which may still be clecoed on from Step 2 when the spar cap holes were already match-drilled to the spar. I'm inclined to remove the spar caps for this final-sized drilling to minimize the chance of accidentally making some of the holes oblong. Anyone see a problem with that?
 
My recollection is I left the spar cap cleco’d on for step four. The doubler and the spar caps only share a certain number of holes. I wanted to make sure that stack up was match drilled through. It is a tad confusing…
 
Paragraph 3 of step 1 seems to talk about this. I added the underline.

Remove the spar cap, deburr the holes of the spar and spar cap, then cleco the spar cap back in place. It's important to deburr and clean out any chips, otherwise the spar cap will not fit
tight against the spar web when match-drilling the spar flange holes.
 
With the spar caps in place I used a #30 reamer which made for a less aggressive final drill.
 
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