Marking out

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For other uses, see Marking out (disambiguation).

Marking out is the process of transferring a design or pattern to a workpiece, as the first step in the manufacturing process. It is performed in many industries or hobbies although in the repetition industries the machine's initial setup is designed to remove the need to mark out every individual piece.

The actual method is unique for each field of expertise, some common areas and their needs are listed below as examples of the variation in an otherwise simple process.

1 Engineering
2 Welding
3 Sheetmetal
4 Woodworking

[edit] Engineering

In the metal trades area, marking out consists of transferring the engineers plan to the workpiece in preparation for the next step, machining or manufacture.

Tools that are peculiar to the engineering area are typically

Surface plate or marking out table — provides a true surface from which to work
Angle plates — assist in holding the workpiece perpendicular to the table
Scriber — is the equivalent of a pen or pencil. It literally scratches the metal surface leaving behind a fine, bright line.
Vernier height gauge or scribing block — allows lines to be scribed at a preset distance, from the tables surface.
Marking blue — to provide a usable writing surface by covering any existing scratches and providing a contrasting background.
Protractor — to assist in the transfer of angular measurements
Combination square — an alternative tool for transferring angular measurements
Square — to transfer 90 ° angles to the workpiece
Punches — either prick or center punch to create permanent marks or dimples for drill bits to start in.
Ball-peen hammer — used in conjunction with the punches to provide the striking blow needed.

[edit] Welding

As welding does not always require the use of fine tolerances, marking out is usually performed by using centre punches, hammers, tape measures and chalk.

The chalk is usually found in the form of small, pre cut blocks of talc. These talc blocks can be sharpened to a stronger point than the softer blackboard chalk, chalk also provides a contrasting color to the hot rolled steel that is generally used.