Popular Woodworking 2002-08 № 129, страница 37
The easiest way to make clean mortises using your drill press is to first drill a series of overlapping holes (right).Then go back and clean up the waste between these holes several times until the bit can slide left to right in the mortise without stopping (far right). Then you only have to square up the ends with a chisel. 12'-long 2 x 8s into manageable lengths. Here's how I did it. With five of the 2 x 8s, crosscut them at 54" and 108". Then rip all the pieces down the middle. This will give you the 20 boards you need to make the top. You then can glue up eight of the shorter fall-off pieces face-to-face to make the bench's four legs, and use the remaining two fall-off pieces for the end rails. With the sixth 2 x 8, you can get the front and back rails, a couple more end rails and have some scrap left over for cutting test joints. If you have a planer and jointer, dress all the wood so it's true and then cut it to final size on your table saw. If you don't have these machines, use your saw to I cut my tenons using a dado stack as shown. I like this method because it requires only one saw setup to make all the cuts on a tenon. First define the tenon's face cheeks and shoulders (right).Then define the edge cheeks and shoulders (below left). Finally, check your work using the test mortise you cut earlier (below right). rip off the rounded edges. Now borrow some extra clamps from your neighbor and make sure you have a lot of glue on hand. It's time to assemble the top. Here's some hard-won advice for you on these tops: Assemble the top a few boards at a time. Yes, it takes longer, but the result will be a top that has no gaps between the boards and is more likely to be flat in the end. Assemble your top using four boards at a time, using plenty of glue and clamps (I needed almost three 8-ounce bottles for the job). Here's one more important tip: If you are going to flatten the top using a hand plane (as opposed to a belt sander), arrange all the boards for the top with the grain running in the same direction. This will reduce any tearout when planing. After the glue has dried on each section, it's a good idea to dress each assembled section of your top with your jointer and planer. This will make assembling the top easier and the end result a lot flatter. If you don't have these machines, be careful during your glue-ups and flatten the entire top at the end. Before you glue all the sections together, pick out the section that will be the front and drill the 3/4"-diameter dog holes now for the front edge. It's much easier now than when the top is assembled. After drilling those dog holes, glue the five sections together, clamp and wait for things to dry. A Mortise-and-tenon Base The base of this bench is built entirely using mortise-and-tenon joints. The two ends are glued and assembled using an old-school process called "drawboring," which I'll show you how to do. The ends are attached to the front and back rails using an unglued mortise-and-tenon joint and bench bolts, which essentially are heavy-duty knockdown hardware that is similar to bed bolts. These bolts are better than any glued joint and can be tightened throughout the life span of the bench. The first step is to make a practice mortise in a piece of scrap that you can use to size all your tenons. I made my mortises on a drill press using a 3/4"-diameter Forstner bit and a fence. You can make amazingly clean mortises this way. See the photos above for details. After you've made your test mortise, head to the table saw to make the tenons. I make my tenons using a dado stack in my table saw. The fence determines the length of the tenon; the height of the dado blades determines the measurement of the tenons' shoulders. Set the height of the dado stack to 5/l6", cut a tenon on some scrap as shown in the photos at left and see if it fits your test mortise. If the fit is firm and smooth, cut all the tenons on the front, back and end rails. Now use your tenons to lay out the locations of your mortises on your legs. Use the diagrams as a guide. Cut your mortises using your drill press. Now get ready to assemble the ends. 36 Popular Woodworking August 2002 |
