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From the pages of Fine Woodworking Magazine Selecting Sheet Goods A furniture maker offers tips for sorting through the stacks of hardwood plywood
You'll most likely have to make decisions about veneer slice, core type, face grade and back grade. I put the highest value on the veneer slice, which is the manner in which the veneer has been cut. The best choices for the exterior are either a plain-sliced or quarter-sliced veneer. Both of these are cut in a straight line, duplicating the figure of sawn lumber. Rotary slicing involves centering the log in a lathe and turning it against a broad cutting knife. The grain pattern does not match that typically found in solid wood.
For a hardwood plywood core, I prefer MDF because there's no chance of a void being telegraphed onto the surface veneers. The face grade will most likely be A if you've chosen plain- or quarter-sliced veneer. It's also helpful to know that veneer-core plywood tends to run a little under its stated size, usually by a light 1/32 in., while MDF core is usually dead-on. I make it a point to talk with a knowledgeable sales clerk and view everything the yard has to offer. You may find a few nice alternatives or surprises. Know your panel dimensions before you shop As you leaf through a stack of plywood, you'll notice that the sheets come in runs, that is, there will be several sheets with veneers from the same log, or flitch. This run might be two or five sheets long. If you ask politely, most places will let you go through the stack to find a run that suits your needs. If you're looking at plain-sliced veneer, it is likely that the veneers will be quite wide. A quarter-sliced stack will most likely consist of narrower veneers. When considering which type of figure suits your piece, consider also where the veneer joints will end up. This means you need to know your panel dimensions before you head out to the lumber dealer. A best-case scenario for a top panel might be a face-grain panel, where two book-matched veneers are wide enough to cover the entire top, with the seam dead-center.
Plywood veneers may not be totally consistent in width. It's usually a small variation but something to watch out for nonetheless. In deciding how many sheets I need, I play it safe. An extra sheet gives me more options when it comes to laying out the cuts. A scratch now is a scratch forever, so choose carefully Hardwood plywood is one of the more expensive items at the lumberyard, and most places try to take good care of it, but dings and scratches are still possible. Commercial veneer is paper thin and easy to sand through. A good rule of thumb is if there is a scratch in it now, there will be a scratch in it forever. So I choose pieces carefully and then accept minor dings as character traits. When I have found what I need, I ask for some of the 4x8 sheets of cardboard used for shipping to protect the material for the ride home and when storing it at my shop. When picking out the interior stock, I'm not as particular. I like to use a light wood like maple. At all of the yards in my area, 1/4-in.-thick maple is available only in rotary-sliced veneer, which means there will be no seams to worry about. Also, I take whichever core is available because small voids won't be noticed on the inside.
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