Moulder Terms

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Moulder Terms:

Moulder: is determined by the number of heads that  a particular machine has. Typically come 4, 5, and 6 head models, although single head models are available. The more heads that a machine has means more material can be removed and more detailed profiles can be produced. Each cutter head is responsible for doing a certain cut. The knives or profiles in head can be changed to fit the desired profile

Flute: one of a series of parallel, lengthwise channels or grooves in a column, cornice molding, band or furniture leg.

Gap: An unfilled opening in a continuous surface of between adjoining surfaces

Hairline: a thin, perceptible line showing at the joint of two pieces of wood.

KCPI: Stands for “knife cuts per inch” generally used when describing the result of molded profiles or S4S materials.

Kerf: The groove or notch made as a saw passes through wood;; also the wood removed by the saw in parting the material.

Knife Marks: the imprints of markings of the machine knives on the surface of dressed lumber.

Machine Bite: A depressed cut of the machine knives at the end of a piece.

Machine Burn: a darkening of the wood due to overheating by machine knives or rollers when pieces are stopped in the machine.

Mill Run: molding run to pattern only, not assembled, machined for assembly, or to cut to length. The terms”material only” and “loose and long” mean the same as “mill run.”

Molded edge: edge of piece machined to any profile other than a square or eased edge

Profile: A trim that has a shaped detail along one or more edges. Eased edges are included in profiles.

Rubber Marks: A raised of hollowed cross-grain cut caused by a sliver between the knife and pressure bar when slicing veneers.

Semi- Exposed Surfaces– Surfaces that are only visible under closer examination

Stops- Generally a molding used to stop a door or window in its from.

S4S- means “ surfaced Four Sides”, and generally refers to the process of reducing nominal sized rough lumber to finish widths and thicknesses.

Wainscot– a lower interior wall surface that contrasts with the wall surface above it. Unless otherwise specified, it shall be 48” in height above the floor.

Tear-out- Unintended removal of material along the grain caused by improper tooling, dull tooling or eradicate grain pattern.

Knicks- imperfection the cutting edge of the knife or cutter head.

Quirk- For purpose of these standards, means a sharp incision in moldings or trim that can hide use of a mechanical fastener.


Base, Base Cap, And Base Shoe

Crown and Coves

Chair Rail


Panel Mold

Hand Rails

Picture Mold

Paneling– including any profile that is utilized on the wall in a vertical pattern or covering the ceiling. Example; bead board, Ship lap, Wainscot, T and G.

Base, Base Cap and Base Shoe– moldings used to trim the intersection of a wall or cabinet and the floor.

Crown, Coves– the decorative molding that conceals the joint between the walls and ceiling , cove a less decorative and tend to be smaller than crowns.

Chair rail– Applied along a wall for protection or as a design element between wall treatments, such as paneling, wallpaper, or paint. (Typically 36” to 48”)

Casing– Generally, a molding placed around a door frame or window frame.

Panel Molds– Small detail molding used as an accent or to mimic a flat panel wall treatment

Hand Rail – in stair work, the member that follows the pitch of the stair for grasping by the hand. Stair hand rails should be mounted in such a manner that the top of the handrails be no less than 34” and no more that 38”

Picture molds– the edge around a framed picture. Also called: picture rail the molding or rail near the top of a wall from which pictures can be hung.

Backed Out ( blackout) – wide, shallow area machined on the back surface of wide solid molding and some frames. Allow the item to span irregular surfaces.

Chatter– Lines appearing across the panel or board at right angles to the grain, giving the appearance of one or more corrugations resulting from bad setting of sanding equipment or planning knives.

Chip Marks– Shallow depressions or indentations on or in the surface of dressed lumber caused by shavings or chips embedded in the surface during dressing.

Concealed Surfaces– surface not visible after installation.

Eased Edges– for the vast majority of work, a sharp arris of edge is not permitted. Such edges are traditionally “eased” by lightly striking the edge with a fine abrasive. Less often, or as a design element, such edges are machined to a small radius.

Exposed surfaces– surfaces normally visible after installation.

Head 1– Responsible for flatten the material. The out feed table is in line with the arc of the cutter head.

Head 2 – Responsible for straighten material, but can also profile material.

Head 3 – Responsible for dimensioning material, but can also profile material.

Head 4 – Responsibilities are determined by the number of heads on the machine. On a 4 head machine it is dimensioning to final thickness and profiling. On a 6 Head machine it is typically surfacing material so that the 5th head is not working as hard.

Head 5– On a 5 head machine the head is on the bottom and is responsible for the any profiling done on the bottom such as grooving or back out or it can be machining a final cleanup. On a 6 head machine it is responsible for profiling on the top material.

Head 6– Responsible for any back profile such as a groove or back out. Can also remove small amount of material for final clean up.

Overview of the molding process.

Machining Process

The timber is machined by the cutting spindles on all four sides while passing through the machine. Each Spindle contributes towards producing the desired profile.

Four Profiled tools are required for four side profiling of the workpiece.

Workpiece Guidance

The timber is guided by the table surface and fences. These are the two fixed reference surfaces for all machine settings.

The infer and outside tables are vertically adjustable for setting the amount of stock removal of the lower spindles.


The bottom straightening and edge jointing spindles serve to machine two rectangular surfaces for proper guidance of the workpiece. All subsequent spindles produce the profile. The spindles are axially and radially adjustable and rotate in a direction opposite to the feed direction.


The feed rollers on the feed beam move the timber through the machine. The feed should be set for the height of the finished timber. The difference between the latter and the height of the unmachined timber is compensated for by the pneumatic system.

Millwork- Grades

Premium– Is selectively used in the most visible and high-profile areas of a project, such as reception counters, boardrooms, and executive areas, providing the highest level of quality in materials workmanship, or installation.

Custom– Is typically specified for adequately covers most high quality architectural woodwork, providing a well defined degree of control over a project’s quality in materials, workmanship, or installation.

Economy– Defines the minimum quality requirements for a projects workmanship, materials, or installation and is typically reserved for woodwork that is not in public

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