Popular Woodworking 2004-04 № 140, страница 44
Mortise &Tenon BASICS A superior way to cut this superlative joint. lot of woodworkers spend a lot of time, effort and money to avoid making mortise-and-tenon joints. Biscuits, dowels, commercial loose-tenon jigs and expensive router bits are just a few of the "work-arounds" developed this century so you don't have to learn to make a mortise and its perfectly matched tenon. But once you learn how straightforward and simple this joint can be, you will use it in every project. Why? Well, it is remarkably strong. A few years ago we decided to pit this venerable and traditional joint against the high-tech super-simple biscuit. So we built two cubes, one using biscuits and one with mortises and tenons. Then we dropped a 50-pound anvil on each cube. The results were eye-opening. Both cubes were destroyed. The biscuit cube exploded on impact. Some of the biscuits held on tightly to the wood, but they pulled away chunks from the mating piece as the joint failed. The second cube survived the first hit with the anvil - the joints held together even though the wood split at the points of im pact. A second hit with the anvil ruined the cube entirely, though most of the tenons stuck tenaciously to their mortises. The lesson here is that biscuits THE 'ANVIL' TEST 1) The anvil is about to hit the cube made using #20 biscuits. 3) The mortise-and-tenon cube held together after the first hit. are indeed tough, but when they fail, they fail catastrophically. The mortise-and-tenon joints fail, too, but they take their time, becoming loose at first rather than 2) The cube made out of biscuits is destroyed on impact. 4) The mortise-and-tenon cube collapsed after the second hit. an immediate pile of splinters. So when you're building for future generations and you know how to make this stout joint with minimal fuss, you won't say "Why bother?" You'll say "Why not?" Choosing the Right Tools There are so many ways to cut this joint that one big obstacle to mastering it is choosing a technique. I've tried many ways to cut this joint - backsaws, commercial table-saw tenon jigs and even the sweet $860 Leigh Frame Mortise and Tenon Jig. Each technique or jig has advantages in economy, speed or accuracy. The technique I'm outlining here is the one I keep coming back to year after year. It uses three tools: a hollow-chisel mor-tiser for the mortises, a dado stack to cut the tenons and a shoulder plane to fine-tune your joints. Yes, this is a little bit of an investment, but once you start using this technique, these tools will become the foundation for much of your joint-making. (For another good way to make this joint, see "Power-tool Joinery," which begins on page 36.) by Christopher Schwarz Comments or questions? Contact Christopher at 513-531-2690 ext. 1407 or chris.schwarz@fwpubs.com. 42 Popular Woodworking April 2004 |
