Here are some verbal descriptions of various molding shapes. I welcome any corrections or additions to these descriptions, particularly the instructions on how to trace the various shapes. In addition, please let me know if you want any other shapes described.
Round Over.
Round Over, is a single convex curve, also known as an ovolo, pronounced O-Vo-Lo. To trace the profile of a round over or ovolo, point your index finger and begin to trace a short horizontal line from left to right and then trace a curve downwards into a vertical line.
Quarter Round
Quarter round is a length of wood that has had a round over molded along one edge. A round under is a single convex curve cut on the under edge of a workpiece.
Beaded Round Over.
A round over with a small step on top and bottom of the curve is made with a beading bit. The small steps are the beads. To trace a round over with a bead on both top and bottom, point your index finger and trace a short horizontal line from left to right, stop with your finger in place, then make a sharp right angle turn down and trace a very short vertical line downwards, stop with your finger in place, then trace continuously a short distance to the right and begin a quarter circle curve downwards until a quarter circle has been traced; stop with your finger in place, then make a sharp right angle turn to the right and trace a short horizontal line; stop and make another sharp right angle down and trace a short line straight down.
Cove
Cove is a single concave curve, also known as a cavetto, pronounced Ca-Vet-Tow. To trace the profile of a cove, point your index finger and begin to trace a horizontal line from left to right, then trace a curve line downwards and then curve that line horizontally to the right.
Bull Nose.
Bull nose is a half circle curve, with or without beginning and ending beads. A simple bull nose is sometimes made by rounding over both the long top corner edge of a board as well as the long bottom corner edge to form a half circle on that long edge of the board. To trace a simple bull nose, point your index finger and trace a horizontal line from left to right and gradually curve the line in a circular fashion downwards until the line is below the point of beginning the circular curve, then continue the line horizontally from right to left. This is often the shape of the edge of a stair treat or window sill. To trace a bull nose with a bead on both top and bottom, point your index finger and trace a short horizontal line from left to right, stop with your finger in place, then make a sharp right angle turn down and trace a very short vertical line downwards, stop with your finger in place, then trace continuously a short distance to the right and begin a circular curve downwards until a half circle has been traced and the line is below the point of beginning that circular curve; stop with your finger in place, then make a sharp right angle turn down and trace a short vertical line straight down. Note: the short horizontal and right angle at the beginning and the short right angle and vertical line at the end are the two beads that characterize the bull nose with beads and distinguish it from the simple bull nose.
Core Box and Round Nose.
Core box is a the curved end of a concave oval and round nose is the curved end of a concave half circle.
Cyma.
Cyma, pronounced sigh-ma, or cyma recta, is a continuous S-shaped curve, consisting of two arcs that curve in opposite sense, concave curve above and convex curve below. To trace the profile of a cyma curve, point your index finger and begin to trace from left to right while curving the line downwards a short distance and then continuously curving to the right again
Ogeee.
Ogee, pronounced O-G, is a continuous S-shaped curve, consisting of two arcs that curve in opposite senses, convex curve above, concave curve below, so that the ends are parallel; also known as a cyma reversa. to trace the profile of an ogee, point your index finger and begin to trace downwards while gradually curving the line to the right until it is almost horizontal and then continuing the curve downwards.
Roman Ogeee.
Roman Ogee, has the same curved form as the ogee, but also has a small right angle step just before the curve begins and another small right angle step just as the curve ends. To trace the profile of a Roman Ogee, point your index finger and begin to trace a short horizontal line from left to right, stop with your finger in place, then make a sharp right angle turn and trace a very short vertical line downwards, stop with your finger in place, then trace continuously a short distance to the right and begin to curve that line downward until the line is vertical and immediately continue in a curve a short distance to the right until the line is horizontal, then stop with your finger in place and and make a sharp right angle turn and trace a short vertical line straight down. Note: the short horizontal and right angle at the beginning and the short right angle and vertical line at the end are the two beads that characterize the Roman ogee and distinguish it from the simple ogee.
Classic Ogeee
A double Roman ogee or classical bit is generally the same except that there is a small step or bead separates the convex curve from the concave curve.
Chanfer
Chamfer is a flat bevel cut off of the square edge of a workpiece. If a groove is cut off of the square edge of a workpiece it is called a hollow and is the same shape as a cove.
Reed.
Reed is a semi-circular convex curve cut into the surface face of a workpiece. The cut is made by removing wood from the edges or sides of the convex portion. Usually there are multiple reeds cut adjacent to each other, such as a double, triple or quadruple reed. Reeds usually have a bead along outer long edges.
Flute.
Flute is a semi-circular concave curve or groove cut into the surface face of a workpiece. The cut is made by removing wood from the center of the concave portion. Usually there are multiple flutes cut adjacent to each other, such as a double, triple or quadruple flute. Flutes usually have a bead along outer long edges.
By Larry Martin