Last edited by John K Jordan 04-26-2020 at 4:19 PM. (I still start the hole with the machinist's center drill or spotting bit. I always pick one of these if I have the right size. I once found a closeout and bought a bunch of taper shank bits for $1 each. For example, look at the length of the same diameter bit in a jacobs chuck and as a taper shank bit, the latter in a #2/#1 morse taper adapter: Using a taper shank bit makes the overall length from the tailstock to the tip of the bit shorter and gives less chance for things to flex and for small inaccuracies to contribute to the bit wandering. These have a morse taper on the end and will either fit directly into the tailstock or fit by means of an adapter for smaller sizes. If possible, forget the Jacobs chuck and drill with taper shank bits. If using a Jacob's chuck in the tailstock, I use the biggest and heaviest I have. If the bit starts to wander, the higher speed and slow drilling can get it back on track as the sharp sides of the flute can shave away the irregularity of a hole that has started to wander a little bit. Drill very slowly, just a bit at a time, backing out often and re-entering to the same depth before drilling deeper. I often run the speed a bit higher when drilling in end grain. If you drill a lot of holes the same diameter, you can even cut one down to make it shorter and stiffer. For a very deep hole I might use four different bits, a center bit, a screw machine bit, a standard drill bit, then an extra long bit to finish. Use one of these to drill as deeply as possible then switch to a longer bit. Search Amazon for screw machine drill bits. These are shorter than "standard" jobbers length bits and wander much less. I bought sets of "screw machine" drill bits. On the same principle, shorter bits are better than longer, at least for drilling the first part of the hole. These sets contain multiple spotting drills in a range of sizes." I sometimes uses these instead of the Center Drills. Also known as hole-starting drill bits or spot drills, these short drill bits have a rigid shank that helps ensure the starter hole is accurate and has clean sides. Another option is a Spotting Bit, like these: From Granger's catalog: " Spotting drills create starter holes that help prevent drill bits from walking (or moving) when the hole is drilled deeper with a drill bit. A longer drill bit can "get off on the wrong foot" at the surface and flex a bit sideways due to the grain, then causes the hole to go further off center as it gets deeper. They are short and stubby and cannot flex so the starting hole is always exactly in the center of the rotation. I pick one a the same size or a bit larger than the drill bit. Start the hole with a machinist's Center Drill. If the outside is turned first the wood itself might flex during drilling. I grip one end of the square stock firmly in a chuck and drill the hole first before turning the handle. I used to have a lot of trouble with the bit wandering, deflected by the grain. I drill a lot of holes in end grain for tool and other handles, some of them fairly deep.
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