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The alignment between the headstock and tailstock of the lathe enables you to drill holes that are precisely centered in a cylindrical piece of stock. I tried doing this once with my drill press and vise before I had the lathe; it did not turn out too well. Before you drill into the end of a workpiece you should first face the end as described in the facing operations section. The next step is to start the drill hole using a center drill - a stiff, stubby drill with a short tip. If you try to drill a hole without first center drilling, the drill will almost certainly wander off center, producing a hole that is oversized and misaligned. We hate that! Center drills come in various sizes such as #00, #0, #1 - #5, etc. You can purchase sets of #1-#5 for under $5.00 on sale from several suppliers.
Preparing to Drill
Before drilling you need to make sure that the drill chuck is firmly seated in the tailstock. With the chuck arbor loosely inserted in the tailstock bore, crank the tailstock bore out about 1/2". Lock the tailstock to the ways, then thrust the chuck firmly back towards the tailstock to firmly seat the arbor in the Morse taper of the tailstock. (The chuck is removed from the tailstock by cranking the tailstock ram back until the arbor is forced out). Choose a center drill with a diameter similar to that of the hole that you intend to drill. Insert the center drill in the jaws of the tailstock chuck and tighten the chuck until the jaws just start to grip the drill. Since the goal is to make the drill as stiff as possible, you don't want it to extend very far from the tip of the jaws. Twist the drill to seat it and dislodge any metal chips or other crud that might keep the drill from seating properly. Now tighten the chuck. It's good practice to use 2 or 3 of the chuck key holes to ensure even tightening (but all three may be impossible to reach given the tight confines of the 7x10). Slide the tailstock along the ways until the tip of the center drill is about 1/4" from the end of the workpiece and tighten the tailstock clamp nut. The locking lever for the tailstock ram should be just snug - not enough to impede the movement of the ram, but enough to ensure that the ram is as rigid as possible.
Unless I'm working with brass, I nearly always use a cutting fluid when drilling. Particularly with aluminum, which tends to grab the drill, this helps to ensure a smooth and accurate hole. I use Tap Magic brand cutting fluid but there are several other excellent brands available.
You only need a few drops at a time, so a small can should last for a long time. I use a small needle tipped bottle to apply fluid to the work. The bottle originally contained light oil & was obtained at Home Depot.
Turn on the lathe and set the speed to around 600 RPM. Use the tailstock crank to advance the drill slowly into the end of the workpiece and continue until the conical section of the center drill is about 3/4ths of the way into the workpiece. This is as far as you need to go with the center...