Fitting
Also called: fitting joints, easing, paring to fit
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Fitting is the work of adjusting one part of a piece so that it sits correctly against its neighbours: easing a door until it swings cleanly in its frame, paring a joint until it seats fully, or cutting a recess so a piece of hardware sits flush. It comes near the end of making something, once the rough shaping is done and the parts have to be brought together.
Tools and general practice
Hand planes are among the tools most used for fitting: they serve to smooth, shape and adjust joints so that the parts finally fit. Once fitting is finished, whatever is left projecting is simply trimmed away. The word covers more ground than it might seem: mitring, cutting two parts to meet at an angle with the joint line splitting that angle, is not confined to joining timber at a right angle and can be applied more widely.
Fitting doors and casements
How much fitting a door or casement, an openable window frame, needs depends on its type. Storm-proof casements sit against the outer surface of their frame and typically need no fitting at all, while traditional casements sit inside the frame and need both fitting and hanging. A traditional casement is fitted by offering its stiles, the upright frame members at the sides, up to the frame and easing them little by little until they fit well; where two casements meet, their stiles are brought together first and the width between the frame's rebates, the L-shaped recesses cut to receive them, is marked onto the hanging stiles at top and bottom. Poor fitting shows up as one of two familiar faults once a door is hung. A door is 'hinge-bound' when its hinge socket, the recess cut to house the hinge, is cut deeper than the hinge's own thickness, and 'screw-bound' when protruding screw heads stop the hinge from closing fully. Some hinge types avoid the problem for lightweight doors simply by needing no recess cut for them at all, which lets them be fitted quickly.
Fitting a joint
A panel's fit shapes which joint is used to hold it, and several rails, the horizontal frame members, and muntins can share a single panel between them. In work with grooved framing, the shoulders, the flat faces cut at right angles to a tenon to seat against the frame, are cut only once the grooving is finished, and fitting begins after that. When a tenon, the projecting tongue of a joint, will not seat properly, the tight side of the tenon or its shoulder is pared down until it does. Chamfering the end of a squared, tight-fitting tenon, called pointing, stops it splitting the sides of the mortise, the slot it fits into, when it is driven home. Fitting a rabbet, a step-shaped recess cut along an edge, mainly means removing wood equal to, or a touch less than, the thickness of the piece that must sit in it. Some joints are checked before gluing: the test cut used to fit a dovetail's tail, the wedge-shaped projecting part of a dovetail joint, can be kept as the fitting reference, or a separate trial piece made instead, and a trial piece of a groove and its mating tail can likewise be cut to check the fit before final glue-up. Dry-wedging, wedging framing together temporarily without glue, holds or checks a piece's shape while it re-dries, rather than forming a finished joint.
Fitting hardware
Door and cabinet hardware each has its own fitting method. A ball catch is usually fitted by boring into the door's closing edge, at either the top or the bottom. A lock plate is fitted by first cutting a recess for the plate itself, then a separate groove behind it for the mechanism. A pin-castor is fitted by driving a solid metal pin into a snug hole, rather than by a screw thread. Not every fitting gets this care: in cheap work, bolts are simply screwed to the back of a door's stiles instead of being flush-fitted, and cheaper furniture, particularly with particle board, has often used screw-in threaded hardware that leaves a visible screw head or cover plate. Interlocking hardware fittings, which mount on hidden surfaces and attach without any machining of the wood, hold less firmly than cam-action fittings, which need the wood machined to take them.
Fitting specialised parts
A staircase's outer string, the shaped board that carries the ends of the treads and risers along its outer edge, is cut to shape with each riser, the vertical board between treads, mitred before final trimming and fitting into the wall string opposite it. Sloping notches are cut to take flanges, projecting edges on a fitted part, with only the flange's own edge needing to sit flush. A low-angle block plane, a small plane held in one hand, suits trimming small parts and works well on end grain, the surface left where the wood is cut across its fibres. For mouldings running around an octagonal shape, woodworkers use the term 'half mitre' for the resulting joint.