Don’t Fight the Fibers Online Extra For a lesson on reading grain from Fine Woodworking’s Mike Pekovich, go to FineWoodworking.com/275. 40 FINE WOODWORKING Photos, except where noted: Asa Christiana COPYRIGHT 2019 by The Taunton Press, Inc. Copying and distribution of this article is not permitted. • Fine Woodworking #275 - May/June 2019 W275RO.indd 40 2/27/19 2:17 PM Work in the right direction Better ways to read grain and Whether you’re surfacing boards by hand or machine, the orientation of the wood fibers makes all the difference. Don’t Fight the Fibers make the most of your lumber WRONG DIRECTION Fibers are pulled upward BY JASON ROBERTS and chunks are torn out of Cutting the surface. motion ike most woodworkers, I’ve learned about grain direc- tion the hard way. I still remember the sound a beautiful piece of spiderwebbed Brazilian rosewood made when L Fiber angle I sent it through a planer with dull knives, nor will I forget seeing it emerge with terrible tearout. I was making a jewelry RIGHT DIRECTION box for my girlfriend, and I nearly wasted that pricey piece Fibers are pushed down Cutting of wood. In the end I had to make the sides much thinner and cut cleanly. motion than I wanted. I’ve now been cutting, drying, and selling high-end lumber for furniture and instruments for more than a decade, and I’ve been making furniture for much longer than that. Along the way I’ve learned a number of reliable ways to read grain Fiber angle and avoid tearout, whether I’m surfacing the wood using power tools or by hand. I’ll help you make the most of your DIFFERENT TOOLS, DIFFERENT DIRECTIONS materials and avoid mistakes reading grain. Planing with the wood fibers means different things on In this article, I’ll refer collectively to the various longitudinal different tools. cells in wood—the ones that grow vertically in the tree—as fiber. Learn how to read the fiber and you’ll head off tearout Plane HANDPLANE before it happens. Even when you can’t prevent it completely, direction you’ll know how to minimize it, making it faster and easier to produce the flat, flawless surfaces that char- Fiber acterize high-end work. angle JOINTER Feed direction Fiber angle Cutterhead rotation PLANER Cutterhead Feed rotation direction Fiber angle TIP Mark the angle, not the direction Roberts marks the fiber angle on the edge of the stock with a short dash. An arrow indicating which way to push For a lesson on reading grain from Fine won’t always work, since the right direction depends on Woodworking’s Mike Pekovich, go to which face you are planing and which tool you’re using. FineWoodworking.com/275. Photos, except where noted: Asa Christiana MAY/JUNE 2019 41 COPYRIGHT 2019 by The Taunton Press, Inc. Copying and distribution of this article is not permitted. • Fine Woodworking #275 - May/June 2019 W275RO.indd 41 2/27/19 2:17 PM It’s the fibers that matter Although growth rings create grain patterns, it’s the Good ways to read orientation of the wood fibers—the various cells that grow vertically in a tree—that matters when it comes fiber direction to cutting. Hardwoods have three types of vertical, or longitudinal, cells: vessels, fiber cells, and tracheids. Roberts takes different approaches Softwoods have just one type, tracheids. A closer look at with different woods, depending on the cellular structure of hardwood reveals a number of which indicators are most visible. reliable indicators of fiber direction. (In softwoods, with no vessels and only microscopic rays, rings are the only guide to fiber direction.) Rings Growth rings are visible on Rings, the circular patterns of a tree’s the edges and faces of many seasonal growth, create prominent lines on woods, and usually are a good the surfaces of a board that can offer a reliable roadmap to fiber direction. indicator of fiber direction. But they are sometimes READ THE FACE misleading. TO PLANE THE EDGE Vessels (pores) grow vertically in the tree, and they Rays are ribbons of cells that can often be seen grow horizontally in the tree, emerging from the radiating out from the center sides of boards. toward the bark, visible in some In large-pored woods but not others. Because woods, they are they are sandwiched between the another dependable longitudinal cells, rays seen on the indicator of fiber face of a board are an excellent Adjacent surface tells direction. indicator of fiber direction. the tale. Roberts read the ring lines on the face of this ash board to figure out which way to joint the edge, achieving a glassy surface as a result. How tearout happens Trees taper as they grow, and tree trunks aren’t always straight. So when boards are cut out of a log, the fibers often run at an angle to the surface. Fiber cells, along with tracheids, are the Wood always wants to split along the fibers. When you plane in the wrong primary structural cells in a tree. However, they direction, tiny splits dive forward and down ahead of the blade and little are very small in diameter and hard to see on chunks of wood lift up and break off, leaving the jagged divots we call tearout. the surface of a board, so you’ll need to look elsewhere to determine fiber direction in a board. Joint, plane, or handplane the board in the right direction, and the fibers will lie down nicely and cut cleanly. Whether the board is riftsawn, quartersawn, or flatsawn, reading the fiber direction and approaching it correctly is the key. 42 FINE WOODWORKING COPYRIGHT 2019 by The Taunton Press, Inc. Copying and distribution of this article is not permitted. • Fine Woodworking #275 - May/June 2019 W275RO.indd 42 3/1/19 1:34 PM READ THE EDGE TO PLANE THE FACE Adjacent surface tells the tale. Roberts read the ring lines on the edge of this ash board to figure out which way to plane the face. When visible, rays and vessels are the Rays and vessels most reliable indicators of fiber direction. Rays Vessels Direction of growth rings Direction of rays and vessels Sometimes the rings don’t tell the story. The rays are always right (if you can see Visible vessels are excellent too. If you Using the rings as a guide when jointing this them). In woods with visible rays, like red oak, can’t see rays, look for vessels (pores). In some oak board resulted in tearout. A close look at white oak, and sycamore, their brown lines are woods, like the butternut shown here, vessels the rays (see photo at right) would have been a a foolproof indicator of fiber direction. Note appear as long, dark dashes. Other woods better bet. how the oval-shaped pores (vessels) agree with with readable pores include birch, walnut, and the rays here, while the growth rings do not. mahogany. Photos, top right this page and opposite, bottom right this page, inset p. 41: Michael Pekovich MAY/JUNE 2019 43 COPYRIGHT 2019 by The Taunton Press, Inc. Copying and distribution of this article is not permitted. • Fine Woodworking #275 - May/June 2019 W275RO.indd 43 2/27/19 2:18 PM Milling difficult woods No matter how great a grain-reader you are, you can’t always avoid tearout. Here’s how to prevent or minimize it on the toughest woods. RAYS CURL INTERLOCKED Rays are a weak point in some Woods like tiger maple get their It’s common for some tropical woods—such as quartersawn oak— luster from the tight undulations hardwoods to have interlocked grain and are prone to tearout no matter of the grain, which can change where adjacent stripes of wood have 1 which direction you plane or cut. direction every ⁄4 in. or less. fibers running in opposite directions. SKEW WHEN JOINTING No good way to go. Figured woods have constantly Use sharp blades and skew the board. Roberts installed sharp knives on his changing grain, which can result in really nasty tearout. jointer, skewed the slab of quilted maple as far as possible to create a shearing cut (top), and got amazing results this time. 44 FINE WOODWORKING Drawings: John Hartman; top three photos, this page: Michael Pekovich COPYRIGHT 2019 by The Taunton Press, Inc. Copying and distribution of this article is not permitted. • Fine Woodworking #275 - May/June 2019 W275RO.indd 44 2/27/19 2:21 PM Of course, wood is an organic material, and not all boards can be planed cleanly in one direction. Trees TRICKS FOR PLANING crook and twist, branches and knots intervene, and grain sometimes changes direction along the length Try wetting the of a board. Some tearout is inevitable. surface. This In fact, some boards are hard to plane cleanly in any works well on the direction. Figured woods are especially tricky, with planer, where the curly figure, burls, and bird’s-eyes. Exotic woods with wet surface faces interlocking grain are also tough. And in some woods up, as opposed to the rays are prone to tearout no matter which direction the jointer, where it would ride the you plane or cut. There are boards with straight grain, cast-iron tables—a mostly parallel to the surface, that won’t tear out no recipe for rust. matter what you do. Air-dried wood is also forgiving, even when it’s figured. There are ways to prevent tearout in even the tricki- est woods, and I’ll cover a few of those.
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