Drilling centered holes in wood.

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How do you guys drill a perfectly centered hole in post and beam construction when you want to fasten your plates? My plates have 3/8" holes and I am using 3/8" decorative lag screws that require a 1/4" pilot hole. I am not much of a woodworker but I'm sure everyone knows how when drilling wood and you start out centered the wood grain pulls your bit off center making your installation crooked or sloppy looking. I thought to use a self centering bit made for drilling cabinet pins that you use with a template that has 3/8" holes in it and the nose of the tool rests in this 3/8" guide hole but the depth is only 3/8" and I need to go to 1.75". I suppose I could go with that and drill the rest freehand. I looked at hinge bits but they have a beveled nose that doesn't fit down snug in a 3/8" hole, and again very shallow depth. I even considered a sleeve bushing that fits the 3/8" hole with a 1/4" hole in it.

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Reply:Yes a bushing or guide will help a lot, assuming it is secured to the work so the bit can't pull it off.Otherwise your best bet are brad point bits. The best ones have nice pointy tips:https://www.rockler.com/37-64-hss-dr...estic-pen-kits-DaveXMT304 with: 22A Feeder, or HF251 Hi Freq DC TIG air cooled
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Originally Posted by bigb

How do you guys drill a perfectly centered hole in post and beam construction when you want to fasten your plates? My plates have 3/8" holes and I am using 3/8" decorative lag screws that require a 1/4" pilot hole. I am not much of a woodworker but I'm sure everyone knows how when drilling wood and you start out centered the wood grain pulls your bit off center making your installation crooked or sloppy looking. I thought to use a self centering bit made for drilling cabinet pins that you use with a template that has 3/8" holes in it and the nose of the tool rests in this 3/8" guide hole but the depth is only 3/8" and I need to go to 1.75". I suppose I could go with that and drill the rest freehand. I looked at hinge bits but they have a beveled nose that doesn't fit down snug in a 3/8" hole, and again very shallow depth. I even considered a sleeve bushing that fits the 3/8" hole with a 1/4" hole in it.