I heard back from Vans this week about the cracked dimples. I was anticipating installing a doubler plate, but their advice was to upsize the holes and install oops-rivets (rivets with a -4 shank and a -3 machine head). I didn’t think upsizing the hole would remove the cracks, but I did it anyway. On one hole the crack was removed, and on the other it was better but still not completely eliminated. I carefully inspected and filed down the dimple slightly to remove the remains of the crack, and plan to install oops rivets tomorrow. I took pictures and emailed to Vans and Jason for a second and third opinion.
I also heard back from Vans on the spar deburring question. Here is their response
Just a quick follow up, Engineering has just given me a written response to your initial question about deburring (or lack thereof) on your wing spar.
Van’s Engineering Response;regarding an RV-14 W-00006C Spar doubler (waffle) plate’s un-deburred edges.
There are considerably higher stress concentrations elsewhere in the spar than along the edges of the spar doubler (waffle plate), e.g. the spar to center section attach holes and the notch in the spar web where the flange terminates. Early version waffle plates were not deburred and were deemed acceptable. Spars were static-tested to 150% of Limit Load (aka Ultimate). Experience has shown that static tests exceeding ultimate loads tend to produce shape failures at locations removed from the main spar. As part of the annual condition inspection, it is required to examine the connection between the wing spar and center section. This would reveal any evidence of fatigue cracking at these higher stress concentrations. Therefore, the un-deburred waffle plate edges are not critical.