Perfect mortise-and-tenon joints require straight, square mortises with flat walls. If you've got the skills, you can chop them out by hand. You also can drill overlapping holes on a drill press or hog out the recess with a router and then square the walls with a chisel. And if your drill press is big enough, you might be able to outfit it with a mortising attachment.
But if you cut mortises regularly and you want efficiency, repeatability and precision, a dedicated mortising machine is just the ticket.
Mortisers are able to cut square holes because they use a hollow chisel with an auger bit inside. The auger bit extends beyond the chisel to remove most of the material, and the chisel follows to square up the walls. After a quick and easy setup, you'll be ready to chop out mortises by the dozen. And dedicated mortisers are built with the power and heft necessary to get the job done – without wearing you out.
Rockler offers great benchtop mortising machines for the home shop, as well as a beefier floor-standing model. And you'll find the necessary accessories, too – from different sizes of hollow chisels and bits to honing tools to keep the chisels sharp.