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Drill the 1/2-in. clearance holes well apart, one about 1-1/2 in. from the top of the framing and one about 1-1/2 in. up from the bottom of the post. You may have to angle the holes slightly to avoid joists, framing anchors or other obstructions. If your drill bit isn’t long enough to go through the post and framing, get a long spade bit. Versions up to 16 in. long are available for $8 at home centers and hardware stores.
Most posts are held fairly plumb by the railing, but check them anyway with a level and tap in shims to straighten them if necessary. Don’t overtighten the bolts; the heads will sink deep into soft wood without much effort.
Photo 1. Drill two 1/2-in. clearance holes through the post and framing. Offset the holes to prevent splitting the post. Angle the hole to avoid joist hangers.
