After doing a not-so-great job countersinking the holes in my HS stringers, I ordered replacement stringer parts and am going to remake them right. But now I’m faced with the problem of how to match drill the new stringers to the already drilled and dimpled skins.
My plan is to skip trying to match drill the stringers to the skins and go straight to countersinking the holes for the dimples.
To do that, I’ll be hoping that the non-match-drilled holes are still large enough to accept the C-sink cutter’s pilot. I think they are, but will be close. If they’re not, I may drill the holes out with something smaller than #40, either a #41, or something smaller, that's just large enough for the pilot to follow but not quite the final size.
Once the holes are countersunk, I plan to go ahead with final assembly of the HS as normal, but check carefully that the skins and stringers line up. Basically, I’m hoping the holes are so close as they come from the factory that they didn’t really need to be match drilled anyway.
But if I find that there are holes that aren’t lining up, I can match drill those at that point during final assembly, since the dimpled skin should fit into the countersunk hole in the stringer flange.
If I do need to match drill a hole or ten, I should be able to reach in and clean up or debur the hole after the fact.
Any thoughts or advice here? Am I going about this all wrong? In general, is this kind of "do-over" fairly common and consequence free? Or is my HS going to look like cr*p and have a bunch of oil canning because the new stringer holes didn't quite line up? (Sure hope not...)
Thanks!
My plan is to skip trying to match drill the stringers to the skins and go straight to countersinking the holes for the dimples.
To do that, I’ll be hoping that the non-match-drilled holes are still large enough to accept the C-sink cutter’s pilot. I think they are, but will be close. If they’re not, I may drill the holes out with something smaller than #40, either a #41, or something smaller, that's just large enough for the pilot to follow but not quite the final size.
Once the holes are countersunk, I plan to go ahead with final assembly of the HS as normal, but check carefully that the skins and stringers line up. Basically, I’m hoping the holes are so close as they come from the factory that they didn’t really need to be match drilled anyway.
But if I find that there are holes that aren’t lining up, I can match drill those at that point during final assembly, since the dimpled skin should fit into the countersunk hole in the stringer flange.
If I do need to match drill a hole or ten, I should be able to reach in and clean up or debur the hole after the fact.
Any thoughts or advice here? Am I going about this all wrong? In general, is this kind of "do-over" fairly common and consequence free? Or is my HS going to look like cr*p and have a bunch of oil canning because the new stringer holes didn't quite line up? (Sure hope not...)
Thanks!
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