Fine Woodworking 2007 Building Furniture

considerations that inform the

design process.

Wood moves freely

in a frame-and-panel door

The simple genius of the

frame-and-panel system is in

making a dimensionally stable

frame of narrow members sur-

rounding a solid-wood panel

that is allowed to expand and

contract freely with changes in

humidity levels.

The panel may be large or

small, plain or simple, but

as long as it is made of solid

wood, it must be given freedom

to move (so that it will not split

or buckle with changes in hu-

midity) and at the same time be

held securely (so that it cannot

warp). Panels are typically held

by their edges in grooves formed

in the surrounding frame, and

they are pinned or glued only

at the center. Occasionally, the

grooves are formed by adding

a strip of molding to a rabbet,

but most often the groove is in-

tegral to the frame.

The frame members are most

commonly mortised and ten-

oned together, although other

methods, such as biscuits or

dowels, can be used (see draw-

ings, p. 95). Because most pan-

els are oriented with their grain

running vertically, the rails have

the most work to do in prevent-

ing the panel from warping.

Therefore, the rails are usually

the widest parts of the frame.

The top rail is often made a

little narrower than the bottom

rail, so that the frame does not

appear top-heavy. The stiles

are generally made narrower

still, giving a pleasing appear-

ance and minimizing the sea-

sonal change in the width of

the door.

The proportions of the frame

joints may vary, depending on

the size and function of the

piece: More substantial doors

should be joined with tenons

approximating one-third of

the thickness of the members;

d e s i g n i n g a d o o r t o l a s t

In a typical frame-and-panel door, the stiles run through from top to bottom, and the grain in the panels

is vertical. The rails are generally wider than the stiles, providing wider tenons and better resistance to

warping of the panels. One rough rule suggests that if the bottom rail is one unit wide, the top rail should

be two-thirds of a unit wide and the stiles one-half of a unit wide.

Center rail

When the Stile

grain of the

panels runs

vertically,

minimal

clearance

is needed

in the rail

grooves; more

clearance is

needed in the

stile grooves

to allow

cross-grain

movement.

All inside edges

are grooved. Mortise-and-

tenon joinery

provides

plenty of

glue surface

and resists

twisting and

Bottom rail racking.

Muntin

Top rail

B a s i c s t r u c t u r e o f a f r a m e - a n d - pa n e l d o o r

Width of

entire door

is subject to

expansion

and

contraction.

Battens fixed

across the

grain result

in cracks

as boards

shrink.

frame-and-panel door

accommodates wood movement

Far smaller

area of

seasonal

expansion

and

contraction.

Frame keeps

panel from

warping or

twisting.

Panel is free

to expand

and contract

within the

frame, so

it will not

crack.

Panel is glued or pinned at its center

only, so dimensional changes occur

equally on both sides.

Solid-plank doors are at the mercy of seasonal changes in humidity. Hence, they are unlikely to fit their

openings in both summer and winter. Frame-and-panel construction solves the problem, making a stable

frame and allowing a solid panel to expand and contract inside it.

plank-and-Batten door

ignores wood movement

W h y F r a m e - a n d - Pa n e l do o r s a r e b e t t e r

Battens can’t

prevent warping

and twisting.

96 F I N E wO Od wOr kI Ng

FWSIP08BF_DF.indd 96 6/6/07 12:31:18 PM