How to Hold a Drill Bit on a Lathe
- 1). Place a drill chuck in a tapered tail stock lathe holder for use in a manual lathe. The pressure of the drilling process holds the drill bit and its assembly firmly against the tail stock drill holder. Slide the drill chuck shaft, which is 1/2 inch in diameter, into the hole, which is also 1/2 inch in diameter, all the way. Place the drill bit in the chuck and tighten with a chuck key and then insert the tapered drill chuck holder in the tail stock.
- 2). Place the drill bit shaft into a 1/2-inch or 3/4-inch collet holder. Drill bits larger than one inch often come with 1/2-inch or 3/4-inch shafts for holding in a collet holder for use in CNC lathes. Place the collet in a collet holder position in the tool turret. Slide the drill bit shaft into the hole in the collet and tighten the retaining screws for the collet. This will clamp down on the collet, squeezing the drill bit shaft tightly for use in a CNC lathe. You can use drill bits over 1 inch in this manner.
- 3). Use a drill chuck in a 1/2-inch or 3/4-inch collet. This is the preferred way to hold drill bits smaller than 1 inch. Slide the collet into a position in the tool turret. Slide the drill chuck shaft into the 1/2-inch or 3/4-inch opening and tighten the screws for the collet in the tool turret. Open the drill chuck with the drill chuck key. Place the drill bit in the jaws and hand tighten it with the chuck key. This will assure that the drill bit will not slide or move when drilling in a CNC lathe.
- 4). Use a collet holder that has a hole the diameter of the drill bit you will use. When you do not have a drill chuck handy, you can use a collet with a small opening for drill bits smaller than 1 inch. They make collets for drill bits of all sizes. For instance, if the you plan on using a .625-inch drill bit, you can use a .625-inch collet to hold the drill bit in place on a lathe. Simply insert the collet, slide the drill bit in the hole and tighten the two screws for the collet.
