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Countersinking Wing Spar

I'm just starting the wings. Things are going well but I'm stuck at 13-03 step 6. I've riveted the wing access plate attach nutplates to the spar after countersinking the rivet holes. The second half of step 6 is to countersink the nutplate screw holes on the spar flange. Figure 4 same page (wing access plate attach countersink detail) provides a drawing of the max inside/outside diameter of the countersink holes. The distance from the edge of the flange to the center of the screw hole in the nutplate is 4.5mm. The plan detail indicates the diameter of the countersink should be 7.8mm. That would mean the distance from the edge of the countersink hole to the edge of the flange would only be 0.6mm. I don't think that is correct. Suggestions?
 
Not sure about the -14 plans, but on the -7 they are dimpled not machine countersunk. Hope that helps.
 
Plans

I'm just starting the wings. Things are going well but I'm stuck at 13-03 step 6. I've riveted the wing access plate attach nutplates to the spar after countersinking the rivet holes. The second half of step 6 is to countersink the nutplate screw holes on the spar flange. Figure 4 same page (wing access plate attach countersink detail) provides a drawing of the max inside/outside diameter of the countersink holes. The distance from the edge of the flange to the center of the screw hole in the nutplate is 4.5mm. The plan detail indicates the diameter of the countersink should be 7.8mm. That would mean the distance from the edge of the countersink hole to the edge of the flange would only be 0.6mm. I don't think that is correct. Suggestions?

I simply followed the plans and everything worked well. Good edge distances for all holes. May want to double check that you are looking at the correct holes, but the plans seemed good to me.
 
I think the wing spars on the -14 must be quite a bit different that the -7. There are more than 1,000 holes on the flanges of the two spars that all need to be countersunk. The spars are way too thick to dimple. Thanks for your reply.
 
Thanks Jon. I followed your link to photos of the main spar dated March 2, 2019. I zoomed in on the middle pic and could see there is very little real estate between the edge of the flange and the edge of the countersink. It looks to be about what I was coming up with. Thanks. I just wanted to make sure before I started making holes.
 
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