{"id":2866,"date":"2014-08-03T09:02:03","date_gmt":"2014-08-03T13:02:03","guid":{"rendered":"https:\/\/mightyrv.com\/?p=2866"},"modified":"2014-08-03T09:51:27","modified_gmt":"2014-08-03T13:51:27","slug":"gotta-do-it-right-the-first-time","status":"publish","type":"post","link":"https:\/\/mightyrv.com\/?p=2866","title":{"rendered":"Gotta do it right the first time&#8230;"},"content":{"rendered":"<p>Carrying on from my <a href=\"https:\/\/mightyrv.com\/?p=2815\" target=\"_blank\">previous post<\/a> &#8211; there&#8217;s one task that RV builders know has to be done right the first time, and that&#8217;s drilling the holes in the aft wing spar that set wing sweep and incidence. I&#8217;ve already covered all the measurements that verify the wings are in the right position and there&#8217;s good edge distance&#8230;now it&#8217;s time to drill.<\/p>\n<p>Van&#8217;s has a <a href=\"http:\/\/www.vansaircraft.com\/pdf\/Wing_%20Incidence.pdf\" target=\"_blank\">good description of the process<\/a> on their Construction FAQ page, so I won&#8217;t repeat their words here. I found a piece of scrap aluminum bar at a local metal dealer and cut pieces to make drill blocks for #30, 3\/16&#8243; and 9\/32&#8243; drill bits and one for a 0.311&#8243; reamer &#8211; to enlarge the hole in stages. The 9\/32&#8243; drill seems like an odd choice, but the ideal use of a reamer is on a hole that&#8217;s about 1\/32&#8243; undersize &#8211; and 9\/32&#8243; is just that for the 0.311&#8243; reamer.<\/p>\n<p><a href=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.25.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-2872\" src=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.25-768x1024.jpg\" alt=\"Rear spar pilot hole drilled\" width=\"584\" height=\"778\" srcset=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.25-768x1024.jpg 768w, https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.25-225x300.jpg 225w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p>The pucker factor was pretty damn high when drilling the #30 pilot holes, but they came out fine &#8211;<\/p>\n<p><a href=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.35.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-2871\" src=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.35-768x1024.jpg\" alt=\"2014-07-24 20.50.35\" width=\"584\" height=\"778\" srcset=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.35-768x1024.jpg 768w, https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-07-24-20.50.35-225x300.jpg 225w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a><\/p>\n<p>I then worked up to 3\/16&#8243;, 9\/32&#8243; and 0.311&#8243; and ended up with good holes in each rear spar.<\/p>\n<p>Enlarging to 3\/16&#8243; wasn&#8217;t too tough, but I was concerned about making sure the 9\/32&#8243; drill block was centered &#8211; don&#8217;t want to eat into the edge distance margin. But then I had a brainwave &#8211; insert a long 3\/16&#8243; pin punch through the 9\/32&#8243; drill block and on into the 3\/16&#8243; pilot hole, and continue until the punch&#8217;s shank hits the side of the drill block hole, centering it on the 3\/16&#8243; hole. \u00a0Clamp the drill block in place, and voila &#8211; the block is centered and ready to use. \u00a0 Here&#8217;s the right side &#8211;<\/p>\n<p><a href=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-15.01.34.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-2867\" src=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-15.01.34-768x1024.jpg\" alt=\"One hole down...\" width=\"584\" height=\"778\" srcset=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-15.01.34-768x1024.jpg 768w, https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-15.01.34-225x300.jpg 225w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a>Here&#8217;s the right rear spar, without an AN5 bolt in place&#8230;<\/p>\n<p><a href=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-17.59.45.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-2870\" src=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-17.59.45-768x1024.jpg\" alt=\"Final-drilled right rear spar\" width=\"584\" height=\"778\" srcset=\"https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-17.59.45-768x1024.jpg 768w, https:\/\/mightyrv.com\/wp-content\/uploads\/2014\/08\/2014-08-02-17.59.45-225x300.jpg 225w\" sizes=\"auto, (max-width: 584px) 100vw, 584px\" \/><\/a>The drill block process worked really well &#8211; finishing the holes with a 0.311&#8243; meant a nice, snug fit for an AN5 bolt &#8211; they went in with only a little finger pressure. \u00a0These bolts are supposed to be be a nominal 5\/16&#8243; diameter, but they often run undersize. Had I used a 5\/16&#8243; reamer, the bolt fit would have been ok, but probably sloppier than I&#8217;d want in this application.<\/p>\n<p>So&#8230;the rear spars are drilled and it&#8217;s a huge relief. I have a backlog of things that need to be done to the wings, like rigging the ailerons and flaps, and it&#8217;s time to make some serious forward progress.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Carrying on from my previous post &#8211; there&#8217;s one task that RV builders know has to be done right the first time, and that&#8217;s drilling the holes in the aft wing spar that set wing sweep and incidence. I&#8217;ve already &hellip; <a href=\"https:\/\/mightyrv.com\/?p=2866\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7,15],"tags":[],"class_list":["post-2866","post","type-post","status-publish","format-standard","hentry","category-fuselage","category-wings"],"_links":{"self":[{"href":"https:\/\/mightyrv.com\/index.php?rest_route=\/wp\/v2\/posts\/2866","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mightyrv.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mightyrv.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mightyrv.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mightyrv.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2866"}],"version-history":[{"count":6,"href":"https:\/\/mightyrv.com\/index.php?rest_route=\/wp\/v2\/posts\/2866\/revisions"}],"predecessor-version":[{"id":2878,"href":"https:\/\/mightyrv.com\/index.php?rest_route=\/wp\/v2\/posts\/2866\/revisions\/2878"}],"wp:attachment":[{"href":"https:\/\/mightyrv.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2866"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mightyrv.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2866"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mightyrv.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2866"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}