Manual of Purpose-Made Woodworking Joinery

Tudor arched shapes 145

TUDOR ARCHED SHAPES

Variable method

90º

H

C

N

A G E J B

F

M

K

L I

Figure 8.7 (a) Tudor arched shape – variable method.

Figure 8.7(a): This method of setting out Tudor arched

shapes is generally regarded as the best method and

can be used to meet a variety of given or chosen rises.

The geometry, which appears complex, is usually mas-

tered when practised a few times.

First, draw the span AB and bisect it to give an

extended centre line through and below E. Mark the

chosen or given rise at C. Draw a vertical line up from

A to give F, equal in height to two- thirds the rise

(CE). Join F to C. At 90° to FC, draw a line down

from C. With a compass setting equal to AF, and A as

centre, transfer F to give G. With the same compass

setting, mark H from C on line CI. Draw a line from

G to H and bisect it; extend the bisecting line down

until it intersects with line CI to give centre I. Draw a

line from I, extended through G on the springing line.

With E as centre, transfer G to give J on the springing

line. Again with E as centre, transfer I, through K, to

strike an arc at L. With K as centre, transfer I to give

centre L. Draw a line from L to extend through J on

the springing line. To form the arched shape, strike

sector- curves AM from G, MC from I, CN from L

and NB from J.

AB, strike the rise at C from A. Alternatively, mark
the chosen or given rise at C from E – which must
not be less than AE or BE. Draw line AC and bisect
to give centre F on the springing line. With centre E,
transfer F to give centre G. Strike sector- curves AC
from F and BC from G.

LANCET GOTHIC ARCHED

SHAPE

G

AEB

F

C

Figure 8.6 (c) Lancet Gothic arched shape.

Figure 8.6(c): The centres for this arched shape are
outside the span, on an extended springing line. First,
bisect the span AB to give the centre line through E.
With a compass set to more than AB, strike the rise at
C from A. Alternatively, mark the chosen or given rise
at C from E. Draw line AC and bisect to give centre
F on the extended springing line. With E as centre,
transfer F to give centre G. Strike sector- curves AC
from F and BC from G. Note that the line AC need
not actually be drawn, once you become geometry-
literate.

C

E

GF

AB

Figure 8.6 (b) Depressed Gothic arched shape.