Popular Woodworking 2009-04 № 175, страница 32
Jointer - No Spring Joint
My approach to edge joining comes from my training in production shops, and my philosophy that a joint under tension increases the chances of failure in the future. 1 don't use a springjoint.and 1 run edges over a well-tuned jointer just before gluing. There isn't anything
/Best face forward. These three pieces came from the same board, and I mill them about16" thicker than I need. I also rip the boards wider - overall the three are alx)ut I" too wide and 3" or 4" too long. When I'm happy with the arrangement visually, I mark part of a triangle on the faces with a lumber crayon.
romantic or inspiring about my approach, but it works well, and it doesn't take long.
I'm a bit persnickety about machine setups, and I get cranky if I have to remember what area of a machine is off a little, and in what direction that offset is. In truth, 1 have trouble remembering things like that, so it's easier to have the jointer knives even with the out feed table and ihe fence square.
1 select wood for panels and tabletops based on appearance. You can't convince me that there is an advantage to alternating growth rings, or arranging the boards so they will be easy to plane later on. The goal is to make a pieced-together board look like it grew that way. If the material is prepared correctly I don't worry about it warping, and if I need to fuss a little when doing the final smoothing, that's OK.
This is an area where master)'ofthe funda
mentals is the key to success. Dead-flat boards with straight and square edgesare easy to put together. Glue them together on a flat surface and it can actually be an enjoyable, relaxing experience. If the boardsare straight and the thickness consistent before gluing, there is little to be done afterwards.
1 crosscut the rough lumber to about the size I need, but when I surface, edge and rip I'm thinking WAP and TAP -"wide as possible" and "thick as possible." This leaves some margin for me to work around defects or ugly spots without starting over. I try to keep parts from a single board together to make it easier to match color and figure.
There may have been a time when a spring joint made sense, especially if the moisture content of the wood was too high. In this day and age, it makes as much sense as collar stays and celluloid dickies. — RL
2 One in, two out. I run each edge to be glued over the jointer, alternating the faces to compensate for any small error in the jointer fence. Keeping track is simple. On the first edge the marked face goes toward the fence. On the next p<ece, the marked face goes out on both edges and on the last piece the marked face goes in.
O Check before gluing. I place the boards *Jj across small strips of wood to make it easier to align the faces, and to keep glue off the benchtop. I make sure these pieces are straight and exactly the same size. If the bench is flat, the support strips equal in thickness and the edges of the parts true, I can squeeze the parts together by hand and not see any gaps.
4 Edges up. I flip the first two pieces up on edge and apply a single head of glue. I don't need to apply glue to both pieces or spread it around. That happens automatically when the parts are clamped together.
5 No wrestling. It doesn't take much pressure to clamp the boards together. My left hand holds the boards down on the support strips to keep the faces in line. A small amount of pressure from the clamp will close the joint for most of the length - if the edges are straight.
6 Clean up immediately. I
scrape off the excess glue, then wipe with a damp rag. If the glue bead dries on the surface, it slows down the drying process, and traps moisture from the glue in the joint. I think it makes a weaker joint.
7 Good to go. The finished glue line is nearly invisible. After letting the glue dry for an hour, the clamps can be removed. Complete curing takes longer, so I let the assembly dry overnight before further surfacing If I do it right, it only takes a few swipes with a card scraper to clean up the panel.
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