Frame-and-panel Finesse Looks and longevity are in the details by Paul Anthony

Frame-and-panel construction for example, it might swell shut without the movement has been used for centuries to during high summer humidity, problems. Whatever style you build cabinet , case sides, and shrink enough to show choose, it’s not hard to build and other assemblies. It is so unsightly gaps during winter’s frame-and-panel assemblies, attractive you might think it was low humidity. With frame-and- especially with the rail and designed that way just for looks. stile bit sets available But it was actually devised as an unglued inside a frame, where it’s these days for the frame elegant solution to the perennial allowedpanel construction, to expand and the contract panel is fit joinery. However, designing problem of wood movement. while the frame maintains a and making assemblies well The problem is that a simple consistent overall size. Brilliant. requires some nuance and a solid wood panel expands and Of course, panels can also be basic understanding of wood contracts across its width in made from , MDF, and movement. Here, I’ve compiled response to seasonal changes in other stable man-made boards. a handful of tips and techniques humidity. So if such single-slab This approach offers the beauty panel was used as a cabinet , of frame-and-panel construction your frame-and-panel work. to help you finesse and perfect

April/May 2014 woodcraftmagazine.com 51 How it works

Door Anatomy Top rail Wood is hygroscopic; that is, it absorbs moisture from the air. And when it does, the moisture swells the cell walls, causing the wood to expand Tongue across its grain. Conversely, when moisture in the air decreases, the wood will shrink across its grain. This response to changing seasonal humidity must be factored into the design of a piece of if it’s to last. Frame- and-panel construction is a solution that Raised fi eld Sti le allows a wide solid wood panel to expand and contract freely within grooves in the frame. The frame consists of stiles (the vertical members) and rails (the horizontals) that are relatively narrow, so they won’t substantially Solid wood change dimension over the seasons. This panel sits dimensionally stable construction houses the unglued in frame panel within the frame grooves. A tongue at grooves. the panel perimeter tucks into the ,

the two even as the panel maintainingchanges a snug width. fit between

Bott om rail into its frame, leave a gap betweenWhen fitting the panel a solid sides panel and No expansion the stile grooves to allow for Wood Movement gap needed in wood movement. (Because rail grooves. the panel won’t change length,

Expansion gap between its rail grooves.) A you can fit it fairly snugly that the fully expanded panel or other proper fit is important to ensure pin through won’t muscle the frame joints rear face keeps apart. Likewise, you don’t want panel centered. a fully contracted panel to pull entirely away from its grooves. In the case of man-made boards (e.g. plywood and MDF), No movement the frame serves to restrain the panel from warping and Solid wood expands and contracts only to hide any ugly edges–all across the grain. the aesthetics borrowed Negligable the while benefiting from movement across from traditional frame-and- grain of narrow panel design. And because sti le and rails. a plywood panel is stable, it can be glued into the frame grooves, making for a virtually No movement indestructible assembly.

52 woodcraftmagazine.com April/May 2014 Frame constructi on Frame joints

Traditi onal Frame stiles and rails should be made from straight- morti se-and-tenon grained stock for both stability and aesthetics. Loose tenon Straight-grained stock is less likely to cause a door to warp, and the straight graining visually accents a panel much better than wild grain. As for the frame joinery, choose an approach that suits the application and your tooling. Keep in Stub tenon relies entirely on the frame joints for its strength, whereasmind that a aplywood door with panel a floating can be solid-wood glued in its panel grooves to increase the overall strength of the door. Sti le-and-rail The time-honored choice is the nearly router bit joint unbreakable mortise-and-tenon joint, whether it incorporates a traditional integral tenon, or a “loose” tenon. A bridle-joint is as strong although less neat because the end-grain of the rail shows. A simpler, but weaker, connection is the stub tenon joint, in which a short tongue on the end this joint a lot for doors with plywood panels becauseof the rail the fits work in the goes stile’s quickly panel and groove. I can Iglue use This sti le and rail bit set the panel in its grooves for great strength. can be used on a router Of course if you have a router table, you can table to quickly and neatly use a rail-and-stile router bit set to create the produce adequately attractive coped stub tenon joints that are so strong frame joinery. ubiquitous in commercial these days.

Panels and profi les

Although most panels can that will shape an attractive simply be categorized as either tongue of consistent thickness. profileFlat panels that terminates of either solid in a woodflat can“raised” make or a “flat,”world the of difference way they’re or plywood can be made in any inprofiled the look and of fitted a frame-and- to their frame thickness. The simplest approach panel assembly. Traditionally, is to make the panel as thick as a tablesawn or hand-planed the width of the frame groove. bevel tapered all the way out to If you want something more substantial, you can either a at the edge to effectively mate centered tongue along the edge of withthe edge, the frame lacking grooves. a flat tongue That’s a thicker panel to center it across why most raised panels made the thickness of the frame, or Top to bott om: Raised panel; in small shops today are cut on create an offset tongue to recess thin fl at panel; thick fl at panel a router table. A wide variety the panel. I usually do the latter with tongue; thick plywood of router bits are available when making plywood panels. panel with off set tongue.

Photos: Paul Anthony; Illustrati ons: John Hartman April/May 2014 woodcraftmagazine.com 53 Composing panels Grain clashes on panel of poorly composed edge- Ideally, a solid-wood panel within uninterrupted, continuous joined boards. a frame should be made from a grain pattern and consistent Wild grain on sti le single board with uninterrupted color. When working with visually distorts grain. However, wide boards can boards that exhibit arched Chaoti c frame, and may compositi on indicate warp- be hard to come by, requiring cathedral grain, it’s a good prone wood. you to glue up large panels from idea to use a full-width board narrower boards. Following a at the center of the panel, and few simple design principles then join narrower straight- can yield panels with gracefully grained pieces to its edges Straight grain on composed grain that makes to create the wider panel. As sti les and rails your furniture stand proud. a general rule, orient the arch makes for stability and an att racti vely When laying out, use long of cathedral grain upward for framed panel. boards, sliding them against each a more uplifting feel. (When Centered other to create a good match at cutting panels from plywood cathedral grain Balanced sheets, select sections of the with upward arch compositi on creates balanced, the boards in whatever way is uplift ing feel. necessarythe edges. Rip,to create flip, and the arrangemost closely as practically possible.) sheets that fit the criteria as

Raising and rabbeti ng panels its grooves. For accuracy, I suggest creating the tongue by making two intersecting cuts Unless you own a shaper, raising use a featherboard to keep the panels is best done on a router table. You’ll want a strong table at the bit location. Also, table.on the Then tablesaw. make Make the second the first cut (minimum 2hp; preferably usepanel a guardpressed to firmlyprotect against your the withcut with the thepanel panel held flat vertically on the variable speed) router to spin hands from that big-ass bit. against the as shown in a typical panel raising bit. When rabbeting the edges the photo below. Orienting the These hefty bits take a big bite, tongue between the blade and so make sure to remove stock grooves, it’s important that the the fence like this ensures it by taking a series of shallow, tongueof a flat be panel a consistent to fit the thickness.frame will be a consistent thickness. sequentially deeper passes. For Otherwise, you invite gaps or clean, accurate cuts, always

problems fitting the panel into

Make the second rabbeti ng cut with the panel held verti cally Use a panel raising bit in your router table to bevel panel edges. The by a featherboard to ensure a guard in the background (See page 20) has been removed for clarity. tongue of consistent thickness.

54 woodcraftmagazine.com April/May 2014 Fitti ng a solid-wood panel

Most seasoned woodworkers plainsawn domestic 1 1 have learned by experience move between 8" and 4" per how much room to allow in stile foot of width from⁄ the driest⁄ grooves to accommodate wood time of year to the wettest. movement of a solid wood panel, Many exotic species move a bit basing their decision on the less, and all quartersawn wood type of wood and the relative moves less than plainsawn. A moisture meter like this humidity in the air. However, Overall, the exact amount of Wagner model MMC 220 will for this approach to work, it’s movement depends on the type accurately tell you the moisture critical that you’re working of species and where you live. content of your stock. with properly seasoned wood, With those parameters in and to be certain of that, you’ll mind, factor in the season and need to read the moisture your locale. For example, if content with a moisture meter. you’re building in the dead of a Precise calculation of wood northeast winter, a 1'-wide panel movement can get complicated, has probably shrunk as much but as a ballpark reference, as it’s going to, so you’ll want 1 remember that most seasoned to leave at least 8" between each edge and its⁄ adjacent stile groove for the wood to expand Tip Alert during the humid summer. Type “Wood movement charts” Conversely, in deep summertime, into your web browser for more you can seat a panel almost informati on on the amount of fully in its stile grooves, leaving To remove enough wood to 1 movement to expect from a perhaps a 16" clearance on allow for expansion, simply specifi c species. each side as⁄ insurance. run a panel’s long-grain edges over the a few ti mes.

Assembly Tips Tip Alert

•

thePre-finish panel shrinks a solid-wood inward panel away before from assemblythe stiles. to • Toprevent prevent exposing buckling non-finished when gluing edges up alater frame, when use parallel jaw clamps. When using pipe

diameter matches the frame thickness. • Useclamps, a dowel flank or the brad stiles to pin with a solid- whose wood panel in place through the back of the rails to ensure the panel stays centered as it expands and contracts. • Because wood movement is not an If you don’t have parallel jaw clamps like the one in issue with plywood panels, they can be the foreground, use proper size dowels against pipe glued into their frame grooves, which jaws to prevent the assembly from buckling. reinforces the overall construction.

April/May 2014 woodcraftmagazine.com 55