SNX-W11-03 Wing Attach Block Drilling

[vernd]

Hi - just about to drill the 4 wing attach blocks in preparation for attaching to W11-05. It appears that these holes and dimensions on W11-05 are critical for later alignment of the spars/wings for drilling. Are there any suggestions for drilling at this point to prevent grief at a some later point of installation of wings. Or just move ahead as per the plans.
I know there's been lots of discussion on related topics already, so would appreciate any learnings from those who have ventured here before.
Thanks much.

Vern

Sonex 613 (Slow scratch build)
Innisfail, AB, Canada

[Sonex1517]

Vern

For the wing blocks I just went per the plans.

I had challenges later but not due to the step you are at.

My two cents

Robbie

[Rynoth]

Drill the wing blocks per the plans. Aim for "snug" fit holes for the AN4 bolts. There's not much debate about this part.

Where there is some debate is how far to take the spar mating process once the main spars are complete. I did mine per the plans. Some would say to mate the spars and drill the attach blocks fully to AN6 size during the spar mating, but I'd do a lot of research before considering this method since it's not what Sonex recommends.

[vernd]

Alright - sounds straight forward. Thanks for the input.
Vern

Sonex 613

[vernd]

I see the plans call for a washer under the bolt head of the AN4 bolts holding wing attach block to the angle. Just curious why the washer would be under the bolt head and not under the nut. Thanks.