Hi!
Why pin them?? It looks terrible!
I have never in my 30 years in this sport/hobby lost a flyÃ*ng surface due to a hinge failing in the air. I either use 5min epoxy for ordinary hinges or for my mylar hinges... Flash thin CA glue + kicker. This is on all kinds of models, large aerobatic birds to 375km/h F3D pylonracers.

Regards!
Jan K
Sweden