Popular Woodworking 2001-08 № 123, страница 33
Mortisers continued from page xx will melt the wax and allow it to run between the auger and chisel. Once you finish cutting a mortise, go back and clean it up by rapidly raising and lowering the head about 1/2" or so and moving the workpiece back and forth. This straightens up a lot of the gunk at the bottom of your mortise. Sharpening If you follow all these instructions and you still have trouble, your bits are probably dull. When it comes to sharpening, the less you do on bits, the better. If you get too aggressive, you can change the geometry of the bit and then you're really in trouble. Err on the side of caution. You can sharpen the chisel bits using a cone that chucks into your drill. It's quick and foolproof, but at a $90 cost. I prefer to touch up my chisel bits with a sharpening stone in the shape of a cone. Stroke only the inside edges of the bit. If you're doing it right, you'll create a burr on the outside edge of the chisel. This needs to be removed, but carefully. To remove the burr, rub each face of the chisel against a fine-grit sharpening stone. Use a single stroke and then feel the edge for the burr. Sharpening the auger bit also requires care. Never file the outside of the bit and never file the center tip. Instead, focus your attention on the two other parts of the bit: the inside of the spurs and the underside of the cutting lip. Sharpen the spurs using an auger bit file, if you've got one. These files have sides that don't have teeth, called "safe" sides. (If you don't have one of these files, you can create a "safe" side on a regular file by covering it temporarily with tape.) File the spurs with the teeth against the spur and the "safe" side against the cutting lip. Try to maintain the same angle as was on the bit before. Now turn to the cutting lip. Touch up the underside of the cutting lip with your file, again maintaining the cutting angle as best you can. Finally, check the shaft of the auger bit for burrs. A burr can cause the bit to seat in the chuck improperly, causing all sorts of trouble. Remove small burrs with sandpaper; take off larger burrs with files. PW 33 Popular Woodworking August 2001 |
