Through tenons and scribed cope joints

by Malcolm MacGregor

The New Hampshire seacoast region where I live was one of the first to be settled by the early colonists. By the 18th century, Portsmouth was a busy port and a commercial center. Local merchants and sea captains invested their wealth in elegant homes, many of which still stand today. Thanks to a renewed interest in restoring these fine homes, about half of my woodworking business consists of making authentic period moldings, sash, trim and doors, mostly with traditional hand tools.

In this article, I'll concentrate on building frame-and-panel entry and passage doors. I'll also discuss the simpler doors found in humbler dwellings or in the less important rooms of more-formal homes. Over the years, I've acquired quite a collection of wooden molding planes, which figure prominently in the hybrid hand/power tool techniques I've developed. For tedious work—thicknessing and ripping stock to size or cutting a dozen mortises—I rely on power tools. But, I make all my moldings and panels with hand-planes. Using the original 18th-century tools ensures authenticity.

There is always a great deal of variation in molding and panel details from house to house. I have at least a dozen thumbnail planes and 15 different panel-raising planes so I can duplicate any 18th-century look. These planes, plus about 400 molding planes, are sharp, set and ready to go: I don't have any time-consuming setup time or wasteful trial runs. For custom restoration work, I can beat any production shop hands down. Also, a hand-cut molding run on straight, clear pine approaches perfection: Corners and fillets are square and sharp and the wood needs iittie or no sanding.

Period door design-When most people think of early woodwork, an elaborately paneled wall complete with crown molding and chair rail comes to mind. But during the mid-1650s to early 1700s, often called the First Period, buildings were not ornate. Common houses were usually of timber-frame construction. Interior partition walls were made of floor-to-ceiling boards whose edges were molded in a pattern called featheredge, which is a very

Drawing Lee Hov

Traditional Furniture Projects 117

shallow, slightly curved bevel or panel section (see figure 1). The featheredge on one board usually fits into a groove in the edge of the neighboring board. Doors were simple affairs. Most consisted of two or more featheredge boards fastened together by clench-nailed battens. Butt hinges weren't widely used until about 1780, so these doors were hung on strap, H-and-L hinges.

I've seen many variations of batten doors, including entry doors made of three or four vertical boards on the exterior side clench-nailed to a layer of horizontal boards on the interior side. This double thickness (about 2 in.) makes a strong, weatherproof exterior door. Many other early doors were a refinement of the featheredge design: The edge of each vertical board was grooved to accept a loose spline, and instead of the featheredge, a bead or shadow molding was run along the joint.

By the 1720s, the early Georgian Period, many colonists could afford more stylish homes. Elegant fireplace surrounds and formal paneled walls and doors embellished with trim inspired by classical Roman architecture came into vogue. Despite the new style, the featheredge paneling and batten doors found use in back rooms and attics well into the 19th century. Georgian paneled doors typically had four or six raised panels set into frames decorated with thumbnail moldings. If the doors themselves were somewhat stylistically uniform, their settings certainly were not. The Georgian style allowed for many variations in trim. The joiner's toolbox and the client's pocketbook actually determined how elaborate the work would be. By the time the style reached its peak around 1770, a formal entry door might have been flanked by stop-fluted Corinthian pilasters capped by an elaborate broken pediment. Similarly, interior architraves (door casings) were trimmed in varying widths of classically derived moldings.

During the Federal Period, which began around 1790, the six-panel door became more widespread in New England. Figure 1 shows the proportions of a typical Federal pattern, commonly known as a Christian door because its frieze rail and intermediate stile form a cross. This design became so popular that it's usually what you'll get today if you order a machine-made paneled wood or steel paneled door. The stiles and rails of Federal doors were usually decorated with ovolo moldings. The panels were both flat and raised, but any raised panels were turned toward the least important side of the door. By about 1820, when the Greek Revival Period began, six-panel doors were still popular, as was the four-panel door shown in figure 1—a design more in keeping with the vertical scale of Greek Revival houses.

Making a paneled door-Despite variations in style, period paneled doors are all constructed the same way: Loose panels are set into a molded rail-and-stile frame, which is held together with wedged-and-pinned tenons, not glue. Apart from the joints themselves, the chief technical problem is mating the molded edges where rail and stile meet. In the modern woodshop, router and shaper cutters can cut a perfect-fitting cope joint in a few seconds. However, they cannot make doors in the traditional manner. These tools didn't exist in the 18th century, so a traditional joiner had to cut the cope by hand, using chisels and an in-cannel gouge whose radius matched the molded profile. I use the same method in my shop.

Before I get into joinery specifics, I'll offer some general comments on the door dimensions given in figure 2. In First Period houses, ceilings were usually quite low, thus it was not unusual to find doors as short as 6 ft. During the Georgian and Federal periods, doors got taller, nearing the usual standard for modern doors-6 ft., 6 in. to 6 ft., 8 in. Widths varied with the application. A typical Georgian passage door ranged from 26 in. to 32 in. in

118 The Best of Fine Woodworking width. The modern standard is 30 in. Main entry doors of the 18di and 19th centuries, aldiough shorter than today's, were often just as wide at 36 in. to 48 in. If you are making a door for a new-house, I'd suggest referring to the local building code. A replacement door should be sized to fit the original opening.

For passage doors, a rail and stile thickness of Vs in. works well with "/i6-in.-thick panels raised on one side, flat on the other. Very few period doors were raised and molded on both sides, primarily, I suspect, because a double mold-and-raise meant both sides of each joint would have to be coped, requiring twice as much work. Because of this, main entry doors are often a composite construction. This is actually two doors in one: a conventional frame-and-panel door clench-nailed to a separate vertical-board door. Besides being quicker to make, a composite door is up to 2 in. thick and is therefore more secure and weatherproof. If I'm making a regular paneled entry door without composite construction, the rails and stiles will be l3/4 in. thick to 2'A in. thick. Single-raised panels are 7/h in. thick; double-raised panels are usually two single-raised panels set back to back.

I begin a door by selecting stock. Period woodwork is almost always painted, so eastern white pine is the wood of choice. Pine is also soft enough to mold nicely widi handplanes and compresses enough at the cope to produce a tight joint. I prefer quartersawn stock, or at least nearly quartersawn, for the rails and stiles because of its stability. In any case, to avoid warping later, select straight boards without wild grain. Figure 2 shows the overall dimensions for a typical Georgian passage door, and these of course, should be varied to match any existing original woodwork.

Layout and joinery—I begin construction by ripping and cross-cutting the rails and stiles. To reduce die chances of their splitting, the stiles should extend 2 in. or 3 in. beyond the mortise. This excess, called a horn, is trimmed flush after assembly. Through tenons are used, so the rails should be cut to a length that equals the total width of the door, plus '/» in. to lA in. for trimming.

The panel grooves are cut first. I do this with a vintage plow-plane, but it can be done with a router or tablesaw. Note that in a door with single-raised panels, the groove is offset, as shown in figure 2, detail A. This means that the molded side of the door has a deeper relief than the back, allowing enough thickness for the molding and positioning the groove so the panel's raised field is flush with the front faces of the rails and stiles. A double-raised door, with moldings on both sides, would be thicker (about 1'/« in.), with the groove centered. Once the groove is plowed, I mold the thumbnail molding with a handplane. This operation can also be done by machine, but to my eye, the results aren't as appealing.

In handwork, it's usual to chop the mortise before making the tenon. Since I use machines for both operations, I find it easier to saw the tenons on the tablesaw first and use them as guides for laying out the mortises. As figure 2, detail C shows, to allow for the cope, the tenon's back shoulder is offset by the exact width of the stile's molded edge, and the cheeks are offset within the stock thickness in such a way that the back cheek aligns with the back of the stile's panel groove. I lay out the '/Win. tenon with a mortise marking gauge, then measure and mark the offset shoulders with a square and knife.

I cut the tenons on the tablesaw, sawing the cheeks first by feeding die stock vertically against die fence. This is not a particularly dangerous operation if you keep die stock perfectly upright and your hands well away from the blade. The cheeks can also be cut using a commercial or shopmade tenoning jig. The offset shoulders also are cut on the tablesaw, using the miter

From Fine Woodworking magazine (July 1988) 71:60-64

Fig. 2: Typical Georgian-period panel door

Lock stile

Wedge top, bottom and lock rails.

Peg locations

Hinge stiie

36 in. to center of lock rail

6 ft., 1 in. to 6 ft., 8 in. typical for passage and entry doors

Detail Lockrail

Detail C

Back shoulder is offset by exact width of molding, Vi in. in this case.

Lock rail

ZVi to

Equals width of stile

Detail A

Listel

Detail B

Cope both sides of joints.

Lock stile

Detail Lockrail

Mortise intermediate stile into 1-in.-deep blind mortise.

Detail B

Hinge stiie

36 in. to center of lock rail

Fig. 2: Typical Georgian-period panel door

Detail A

Listel

Cope both sides of joints.

Lock stile

6 ft., 1 in. to 6 ft., 8 in. typical for passage and entry doors

Mortise intermediate stile into 1-in.-deep blind mortise.

Detail C

Back shoulder is offset by exact width of molding, Vi in. in this case.

ZVi to

Equals width of stile

Lock stile

Wedge top, bottom and lock rails.

Peg locations

Lock rail

Rail And Stile Plane

After the stock is ripped and cut to length, grooves for the panels are plowed with an 18th-century plow plane, above. The same operation can be done with a router or on the tablesaw. Left, the rails (and intermediate stiles) are tenoned on the tablesaw. The cheeks are cut first by feeding the stock vertically against the fence. Because the blade's vertical reach is limited, wasting up to the shoulder is done with multiple crosscuts, which are then pared off. The cope on the molded rail, right, is cut with a '/i in. in-cannel, in a series of shallow, slicing cuts. To ease the fit, ifs undercut slightly.

gauge and with a stop block clamped to the fence, as shown in the photo above. Through tenons for doors are as long as the stiles are wide (usually at least 4 in.)—quite a bit more dian a 10-in. tablesaw can cut vertically. To finish off the cheek, I make closely spaced multiple cuts when I saw the shoulders and then pare off the waste with a slick or chisel. The width of the tenons isn't critical, but traditionally, the wide lock rail has a pair of side-by-side tenons instead of a single wide one. Some craftsmen believe this is for wood movement, but I think the real reason is that the load in a door is carried not by the tenon cheeks, but by the top and bottom edges of the tenons. The more tenons, the stronger the door will be. Also, the space between the tenons leaves wood tor the lock set to be mortised into, without weakening the joint.

After cutting the tenons, I position the rails where they'll join the stiles and mark the mortises directly from the tenons. With the same marking gauge setting I use for the tenons, 1 mark each mortise position on the outside edges of the stiles too. This way, when 1 cut the through mortise with a hollow chisel on the drill press, I can cut in from both sides. To allow room for wedges, the mortises should be about % in. longer than die tenons. While die mortiser is set up, I cut the blind mortises for the intermediate stiles, as shown in figure 2, detail B. The intermediate stiles themselves are cut to length and tenoned after the principal frame copes are cut and .the door is test-assembled.

Cutting a hand cope—Two moldings can he joined at a corner by cutting or coping one to the exact reverse section of the other, allowing the moldings to nest together. It's time-consuming, but not difficult if you have a sharp in-cannel gouge (mine is Vi in. radius) that closely matches the molding profile. Before coping on a door, I'd suggest a few practice joints. I begin by using a chisel to pare off the molding on the stiles where the rails will meet them, as shown both in the photo above and in figure 2, detail D. The molding is pared off to a depth even with its fillet or listel.

I mark out the cope cut with a miter square. Although the joint isn't really a miter, it looks like one when it's done, and a 45° angle closely approximates the correct profile. The layout line (and the cut itself) should just intersect the very end of the rail at the point where the molding's listel or fillet meets the tenon's shoulder. Cut the cope with a series of shallow paring cuts until your gouge just reaches the layout line, then try the joint. Undercutting a bit as you approach the line will provide some extra clearance. If the cope won't seat, the offset back shoulder needs to be trimmed back a little with a shoulder plane. If the cope seats with an open back shoulder, deepen the cope until the shoulder pulls down. Remember, soft pine will compress at the cope, so a hairline opening at the back shoulder usually isn't a problem. Use the same method to fit the two copes that mate the intermediate stiles to the lock rail.

With the copes done, I test-assemble the door and check for proper fits. Test the door's squareness by measuring diagonally from corner to corner. There should be enough play in the joints to make minor adjustments. At this point. I measure between the top. bottom and lock rails, fillet to fillet, and add 3 in. to get the exact length of the intermediate stiles, which I then tenon and

Woodworking The Right Technique

MacGregor's associate, Stu Worthing, assembles the door. Assembly proceeds from the inside out by first inserting the intermediate stiles into the lock rail, followed by the panels and the top and bottom rails. Last in place are the lock and hinge stiles.

Measure Squareness
Above, wedges and pins lock the tenons securely without glue. The wedges are driven in above and below the tenons until they seat firmly. Below, pins made from rounded square stock are driven into 'U-in. through-bored holes.

cope. The tenons are 1 '/> in. long. When all the rails and stiles are in place, I determine panel sizes by measuring the actual frame openings, again fillet to fillet. I allow '/i6 in. on the length and nothing to % in. on the width, depending on the season, to allow for wood movement. I raise the panels with a wooden plane (see the profile in figure 2), but this operation can be done with machines as well (for example, with a router with a fence extension and a shopmade jig). After trying the panels in their grooves, 1 smooth-plane the fields, rails and stiles and sand as needed.

Final assembly -Since the door won't be glued, you can proceed directly from test assembly with the panels in place to wedging and pinning the tenons, assuming everything fits. You might be tempted to glue the tenons, but there's no need. I've seen old doors that have stood up to two centuries of wear and weather without a drop of glue.

I begin by clamping the door lengthwise to pull the intermediate stiles tightly against their shoulders. The intermediate stiles are not wedged or pinned, so the tightness of their shoulders depends on their being held slightly in compression against the lock rail. Clamps placed widthwise pull the rails home. With the clamps still in place, I use a razor knife to slice wedges from a scrap as thick and as long as the tenons. The wedges taper from about J/i6 in. to perhaps % in. and are driven in at the top and bottom of each tenon. I tap the wedges in as far as they'll go without breaking off, then trim them flush with a hacksaw. To further lock the joint, each tenon is pinned with a pair of round-cornered square pegs driven into a 'A-in. hole bored through both mortise-and-tenon cheeks.

To finish up. pare the pegs flush, finish the stiles and rails with a smooth plane and cut the horns off. The door is now ready to hang. Once hung, a couple of coats of primer followed by a coat or two of good-quality oil paint completes the job.

Malcolm MacGregor operates Piscalac/tta Architectural Woodwork Co., in Durham. N.H. For more on doors, see FWW on Joinery.

Antebellum Furniture ReproductionsPegged Pinned Tenon

The author builds period reproduction mantels, such as the one shown here, using antebellum mantels as inspiration. This blockfront mantel incorporates grooved pilasters, raised panels and a variety of moldings made with simple milling procedures.

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Responses

  • gennaro
    How to make feather edge boards waterproof?
    3 years ago
  • VELI RINTANEN
    How can you reduce the width of a panel door?
    3 years ago
  • robinia
    What is a lock rail door?
    2 years ago

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