Moulding
Also called: sticking, running mouldings
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Moulding is a shaped, usually curved, profile worked along the edge or face of a piece of wood, cut either to decorate it or to cover a joint. Most moulding is still worked in solid wood, though MDF, a manufactured board made from compressed wood fibre, and low-density foamed plastics see some limited use as alternative materials.
Cutting the profile
A moulding plane is the traditional tool for the job. When shaping a profile by hand it helps to strip away the bulk of the waste beforehand with a plough plane, which cuts a groove running with the grain, or with a rebate plane, since both of these keep a sharp edge for longer than a moulding plane does. Running a moulding by hand is finished once the plane's sole rubs against the finished surface of the moulding while its back fence, the guide running along the far side of the plane, still rides on unworked wood. Full sets of moulding planes have grown scarce in workshops today, and new ones are hard to track down, which has kept a place for the scratch stock, a small tool that scrapes a profile rather than cutting it in shavings: it still earns its keep for scoring the narrow grooves used in inlay work, though it falls short on any profile with real depth to it, and before it settled into that narrower role it commonly stood in for a moulding plane, shaping small profiles whenever the right plane could not be had. On the spindle moulder, a machine that spins a shaped cutter to form the profile, cutting a moulding in two passes is the normal approach, so as to avoid the strain of one heavy cut.
Mouldings on mortise-and-tenon frames
There is an order to follow on a moulded frame member. The profile is shaped into the stock's inner face edge before anything else is cut, and only then are the rabbet, a stepped rectangular recess, and the haunched mortise, a mortise cut for a tenon left with a short filling stub, brought down flush with that shaped edge; later, at the point where the moulding actually crosses the mortise, its own profile is pared away last of all, flush with the mortise opening. Door frames built with mortise-and-tenon joints and mitred lengths of sticking, the continuous run of moulding worked along a frame member, hold up well, and when drawing up a cutting list for rails carrying this kind of moulding, the sticking's width has to be added onto both ends of the finished rail length. A bandsaw run against a fence is one way to strip sticking back off a stile, the upright side member of a frame. To scribe a moulded frame, cutting one piece so it follows the profile of the piece it meets, the moulding on the mortised piece is cut back to leave a square shoulder, a flat step cut at right angles for the other piece to sit against, and the tenon shoulders on the matching piece are scribed to that same profile. A chisel guide, a block that keeps the chisel running along the correct line, makes it easier to bring the pair of halves in a mitred moulding joint into true alignment, and sinkings, the recesses cut to take a moulded profile, are best left slightly large, with the final fit brought home precisely afterward using a shoulder plane and a moulding plane.
Mitring, coping and fitting moulding
A mitre in a moulding needs both lengths to share the same profile. On a chair rail, a moulded rail fixed along a wall at the height of a chair back, the upper and lower members share the same profile as the matching wall or back moulding, which is what lets the two mitre together where they meet. A raking moulding, one that runs at a slope, needs a different profile from the horizontal moulding it meets if the mitre where they cross is to line up truly. Wide mouldings, and curved mitre work such as a door with curved mitres, can run into trouble: the bisecting cut of the mitre may meet before it has cleared the moulding's full width, forcing the angle to be cut again. A bolection moulding, a wide, thick moulding rebated over the edge of a panel's frame, is fixed to the panel itself rather than to the frame, because its own width and thickness demand it, and this arrangement also keeps the gaps left by the panel's shrinkage out of sight. A scotia, a concave moulding profile, is used mainly on bases. Some moulding profiles carry an undercut worked into them, a step cut back from the visible face, which lets the moulding sit close where a floor meets a wall.
Working with lengths of moulding
When cutting a moulding to length, a little extra is left beyond the mark for final planing; one method mitres one end first, then lays the piece against a reference mark to gauge where the rest should be cut. A tenon saw, a fine-toothed saw with a stiffening back edge, can cut straight through a moulding profile, and where no other route is open, a steady hand and a well-sharpened saw let a joint be cut cleanly from behind the moulding instead. Getting rid of a section of moulding that is not wanted can be done by making a run of saw cuts across the grain and then paring the waste away, working down to the level of the rebate underneath. A moulding fitted with handles sometimes has notches cut into it first to seat them, and the handles are then fixed in place with screws.