‘To draw the several kinds of mouldings made by Joiners’

Kale and I had a brief discussion of mouldings and moulding planes last week as she worked on her tool chest, and raised a square panel for one piece using a rabbet plane. And that reminded me of Peter Nicholson’s discussion of moulding profiles, which I love in large part because of the mellifluous nomenclature. Scotia. Quirk. Cavetto. Astragal. Yum. Here is part of that text, which teaches you how to draw a handful of profiles, excerpted from our reprint of “Mechanic’s Companion.”

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§ 68. To draw the several kinds of Mouldings made by Joiners.

An astragal is a moulding of a semi-circular profile; its construction is so simple that it would be unnecessary to say anything concerning it. Fig. 1. [Editor’s note: Ha.]

There are two kinds of beads, one is called a cocked bead, when it projects beyond the surface to which it is attached, see Fig. 2; and the other is called a sunk bead, when the sinking is depressed beneath the surface of the material to which it is at­tached, that is, when the most prominent part of the bead is in the same surface with that of the material, Fig. 3.

A torus in architecture is a moulding of the same profile as a bead; the only difference is, when the two are combined in the same piece of work, the torus is of greater magnitude, as Fig. 4; in Joinery the torus is always accompanied with a fillet. Fig. 5. single torus moulding.

The Roman ovolo or quarter round, as called by joiners, is the quadrant of a circle, Fig. 6. When the projection and height are unequal, as in Fig. 7, take the height B C, and from the point B describe an arc at C, and with the same radius from A, describe another arc cutting the former at D, with the distance A D or D B describe the profile A B. This is generally accompanied with fillets above and below, as in Fig. 7.

The cavetto is a concave moulding, the regular profile of which is the quadrant of a circle, Fig. 8; its description is the same as the ovolo.

A scotia is a concave moulding receding at the top, and pro­jecting at the bottom, which in this respect is contrary both to the ovolo and cavetto; it is also to be observed, that its profile consists of two quadrants of circles of different radii, or it may be consi­dered as a semi-ellipse taken upon two conjugate diameters, Fig. 9.

To describe the scotia, divide the height A B into three equal parts, at the point 2 draw the line 2 C D, being one-third from the top, draw E C perpendicular to C D, with the centre C and distance C E describe the quadrant E F; take the height A 2 and make F D equal to it: draw D G perpendicular to F D, from D with the distance D F describe the arc F G, and E F G will be the profile of the scotia. This moulding is peculiarly applied to the bases of columns, and makes a distinguishing line of shadow between the torii.

The ogee is a moulding of contrary curvature, and is of two kinds: when the profile of the projecting part is concave, and consequently the receding part convex, the ogee is called a cima-recta, Figs. 10 and 11 ; and when the contrary, it is then called a cima-reversa, Fig. 12.

To describe the cima-recta when the projection of the moulding is equal to its height, and when required to be of a thick curvature, Fig. 10. Join the projections of the fillets A and B by the straight line A B; bisect A B at C, draw E C D parallel to the fillet F A, draw A D and B E perpendicular to F B; from the point E describe the quadrant B C, and from the point D describe the quadrant A C, then B C A is the profile.

To describe the cima-recta when the height and projection are unequal, and when it is required to be of a flat curvature, Fig. 11. Join A B and bisect it in C, with the distance B C or C A from the point A describe the arc C D, from C with the same radius describe the arc A D cutting the former in D, the foot of the compass still remaining in C describe the arc B E, from B with the same radius describe the arc C E, from the point D describe the arc A C, from the point E describe the arc C B, then will A C B be the profile required.

The cima-reversa, Fig. 12, is described in the same manner.

Quirk mouldings sometimes occasion confusion as to their figure particularly when removed from the eye, so as frequently to make one moulding appear as two.