Using something like the Simpson Strong-Tie ABU post base, what is the procedure to ensure that the post is plumb when securing with 1/2 in in bolts? Is it reasonable to tack the post plumb and attempt to squarely drill out 1/2 in in holes on center? Or is the typical approach to drill oversized holes (say, 5/8in) and then use the play to plumb up the post before tightening the bolts? Also, how do you typically ensure that the through holes are drilled perpendicularly?
No matter how, or with what you attach the post it will have some give and not be perfectly plumb. So while you want to do the best you can there should not be great worry over getting holes perfect. They should not be a mess either.
I have set my post and marked the holes with circles. Removed the post to the ground or saw horses and draw a straight line across the post bisecting the marked holes and continuing all the way around.
Then drill a hole the same size as the bolt being used. ( Not oversized) Being careful to guide the drill straight with the drawn line.
Sometimes it can help if you have a drill with a built-in level. However this is useful only if the holes in the brace are perfectly level as well.
