Popular Woodworking 2007-08 № 163, страница 8
In Search of Bench Dog Perfection I'm currently building a traditional-style workbench with tail and face vises. I was hoping you could offer some advice on the drilling of bench dog holes. I will be using round bench dogs (3A"). I am sincerely hoping that there is a way to do them on the drill press before laminating the top, because I have had difficulty drilling perfectly vertical holes with a brace in the past. I would be using my brace due to the shank size of my 3A" bit. Do you have a process for drilling these large holes and keeping them true? —Jeff Hallam, Kingston, Nova Scotia I've done it two ways: One: Laminate a few boards for the top, drill the holes on the drill press as shown below then laminate the rest of the top around that. The technique works great. Two: Make a simple jig. It's a bit like a dowel-ingjig and is made with three pieces of stock. One thick piece guides the drill bit, one piece registers off the front edge of the workbench like a fence. And the third piece is aflat piece of plywood that ties them both together. It looks a bit like a bench hook with an over-sizedfence. Either way, I use a 3/4" auger bit and a corded drill (or a brace and bit if I'm feeling frisky). — Christopher Schwarz, editor Mitered Frame Construction Must Allow for Seasonal Movement I am building a couple tabletops with the largest measuring approximately 36" x 36"". I would like to have a mitered frame and then fill the inside with solid wood as well. I am using sassafras (this is what I have the most of), but I am concerned about gluing or joining all of the pieces because of expansion/contraction. The wood has been stored in my basement, which is heated and fairly dry, for about four years. Do I need to "float the insides" or can I glue it all together? —Jim Somers, Sparta, Ohio The mitered frame surrounding a solid panel is something many people want to do, but you need to keep in mind that the solid panel will expand and contract with seasonal changes in relative humidity. Sassafras is fairly stable, but you could still expect movement of 1/s" per 12" of width, or about 3/s" in your 36" x 36" top. If you don't allow for this, the top will self-destruct. When I lived in the Cleveland area, the dead ofwinter was the driest time ofyear. Ifyou made this top in the winter, it would expand the following summer and would force the joints apart at about the time the Indians are eliminated from the pennant race. If you put the top together in July or August, when the wood has reached its maximum moisture content, it would start shrinking when the furnace came on in the fall and would crack by the time the Browns get the first pick in the following year's NFL draft. You can float the top in grooves in the frame, butyou will need to leave a gap between the panel and the frame. The size of this gap will depend on the moisture content of the wood in the panel and whether it is likely to shrink or expand. You could also hold the individual boards in the top together with splines in grooves, leaving gaps in between the boards. Ifyou want a nice tight joint where the panel meets the frame I would recommend veneering a plywood or MDF panel. — Robert W. Lang, senior editor Why No Biscuits in Laminations? In researching designs and techniques for a workbench, I noticed that you do not use biscuits to align the laminations when gluing up narrow boards to make a benchtop. I'm sure there is a reason for this but I seem to have missed it. Can you please explain? — Ted Mock, Toronto, Canada I don't use biscuits when gluing up long-grain joints. They do not add strength (the bond is already stronger than the wood itself). And I have found that user error can or will create alignment problems that the biscuits were supposed to help avoid. I just glue and go. Clamp from the middle of the lamination and work out. Shift the boards around until they are aligned. Be done with it. However, ifyou like to use biscuits, are comfortable with them, and are accurate with them, then also know that they won't hurt the joint's strength. — Christopher Schwarz, editor What's the Best Angle of Attack For Planing Figured Woods? I own a Lie-Nielsen low-angle jack plane, a Lie-Nielsen shoulder plane and a Lee Valley cabinet scraper. I am building a bedroom suite and my skills have evolved significantly as I have slowly built this collection of furniture. On my last piece, I was determined to use my hand tools to eliminate as much sanding as possible and improve my overall work flow. Unfortunately, things didn't go well. I tuned up my jack plane and set to work. The tear-out on my curly maple was bad, and the swirling grain on my cherry went from great to unacceptable every few inches. Talk about frustrated. My cabinet scraper gave me good results on the cherry but couldn't handle the fid-dleback curly maple well enough to avoid all tear-out. So, I'm going to a woodworking show and am planning to buy some more hand tools. I'm considering a Lie-Nielsen block plane and Lie-Nielsen smooth plane. But which smoother should I get? I love figured woods so I think a high-angle frog is a good option. I was thinking a corrugated base would help offset the extra effort of the high-angle frog. But should I get the No. 4 or the No. 4V2? Lie-Nielsen recommended a No. 4V2 but in your "Hand Tools In the Modern Shop" I recently ordered (available through the Store at popularwoodworking. com), I noticed you are currently using a No. 4. So, for a person with a limited arse popularwoodworking.com ■ 13 |
