Locating Hinges and Locksets To avoid confusion and save time, mark the hinge and lockset layout while the door is standing near the opening. To locate the hinges, pull a tape measure down the hinge side of the jamb (Figure 2).

Figure 2. Measure to locate the top of the existing hinges and write the dimensions lightly on the door. To reduce math errors, the author prefers to leave a gap between the tape and the head jamb rather than holding the tape tight to the jamb and subtracting 1/8 inch.

Touch the top of the tape measure against the top of the jamb, then slide it down almost 1/8 inch — the standard gap between the top of the door and the top of the jamb. (I prefer to slide the tape down instead of subtracting from the measurement at each hinge because it reduces mistakes — and it usually takes longer to correct mistakes than to hang the door.) Holding the tape tightly with one finger, measure to the top of each existing hinge mortise — this is exactly where the hinges should be placed on the new door. Write the measurements lightly on the face of the door near each hinge location, or on a scrap of paper. To locate the lockset, measure down the strike side of the jamb to the center of the strike and subtract 1/8 inch for the head gap. Again, note the dimension on the door, near the location of the lockset. On raised panel doors, I like to center the lockset in the lock rail. If the old strike mortise in the jamb doesn’t align with the lock rail of the new door, I’d rather move the existing strike mortise on the jamb than have the lockset look out of center in the door. On a painted jamb, I’ll fill the strike mortise, but on a stain-grade jamb either the door must be drilled to match the strike mortise in the jamb, or the jamb must be replaced.

Cutting Down the Door

I do all cutting, drilling, and planing of the door on a work bench especially made for the purpose (see ). The bench holds the door either flat or on edge, and it also provides a storage area for my door-hanging tools.

Top and bottom cuts.

Because circular saws cause tearout and chip end grain, use a square and a utility knife to score a line across the face of the lock and hinge stiles. (For flush doors with veneered skins, score a line completely across the door.) I also score the far edge of the door, where the saw blade will exit, to eliminate tearout on the back of the stile. While the bottom of the door can be cut quickly with a circular saw, the top has to be cut very straight — if the saw tips even slightly, the gap between the top of the door and the jamb will be uneven. One trick is to cut just outside the pencil line, then use an electric door plane to finish the cut right to the line (Figure 3).

	Figure 3. To ensure an even reveal at the top of the door, cut close to the scribe line with a circular saw, but finish the job with a power plane. To avoid tearout at the edges, hold the plane upside down and work the first 6 inches of the rail from one side (top), then flip the plane over and finish planing from the other side (bottom).

To eliminate tearout, start by holding the plane upside down and come in from the far side of the door. It’s essential to keep pressure on the fence beneath the door to make sure the plane stays square with the top of the door. But because this is awkward, I plane only about 6 inches into the door right to the pencil line, then turn the plane around and come in from the opposite end of the door to finish the cut.