I generally follow "The Rules", or stay inside "the Box" as my wife likes to say. However, after a particularly bad experience with countersinking some holes, I decided to attempt dimpling instead.
The setup: See page 9-10 of the RV-14 Empennage plans if you'd like to follow along. The plans call out for countersinking the top flange of the rear spar (E-00907-1L) along the section where the trim tab hinge mounts.
Situation:
My handy-dandy-good-for-drilling-wood-only-Dewalt drill motor has excessive run-out; I know this, but I proceeded using it along with the micro-stop countersink cage and created a bunch of **** "snow-men" countersunk holes in the rear spar. Into the recycle bin with ya...but wait...
Idea:
More deviation from plans -- Van's supplies MS20257 hinge, which I do not like - especially for flight surfaces, so I had ordered MS20001 to use for the trim tab attach.
Instead of countersinking the replacement spar in the aforementioned area, I am going to dimple it, and dimple the underlying hinge material. The test I did on the buggered up rear spar and scrap hinge seemed to work well. Dimpling the hinge material requires a little "ooomph" but easily accomplished with C-Frame or DRDT-2 or Pneumatic Squeezer.
Aside from the "difficulty" in dimpling this hinge material (it's .056" for the MS20001 and .040" for the MS20257), anyone see a reason dimpling this stack up is a bad/unsafe idea?
The setup: See page 9-10 of the RV-14 Empennage plans if you'd like to follow along. The plans call out for countersinking the top flange of the rear spar (E-00907-1L) along the section where the trim tab hinge mounts.
Situation:
My handy-dandy-good-for-drilling-wood-only-Dewalt drill motor has excessive run-out; I know this, but I proceeded using it along with the micro-stop countersink cage and created a bunch of **** "snow-men" countersunk holes in the rear spar. Into the recycle bin with ya...but wait...
Idea:
More deviation from plans -- Van's supplies MS20257 hinge, which I do not like - especially for flight surfaces, so I had ordered MS20001 to use for the trim tab attach.
Instead of countersinking the replacement spar in the aforementioned area, I am going to dimple it, and dimple the underlying hinge material. The test I did on the buggered up rear spar and scrap hinge seemed to work well. Dimpling the hinge material requires a little "ooomph" but easily accomplished with C-Frame or DRDT-2 or Pneumatic Squeezer.
Aside from the "difficulty" in dimpling this hinge material (it's .056" for the MS20001 and .040" for the MS20257), anyone see a reason dimpling this stack up is a bad/unsafe idea?
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