Irwin Marples M2153 Mortice & Marking Gauge

A marking gauge typically has one point (spur) for marking a single line parallel to an edge. A mortice gauge has two parallel spurs, allowing it to mark both sides of a mortise simultaneously.

While the gauge is designed for wood, it might mark softer plastics. It is not intended for use on metal.

Loosen the knurled brass thumbscrew to allow the stock to slide. Position the spur to your desired measurement and then retighten the thumbscrew securely.

The 'extra spur' refers to the second parallel spur used in the mortice gauge configuration. The main spur is the one used when the tool functions solely as a marking gauge.

Sealed rosewood is quite durable for its intended use, providing a good grip and resistance to general workshop conditions. However, like any natural material, it can be damaged by excessive force or impact.

Brass can tarnish over time due to exposure to air and moisture. Regular cleaning with a brass cleaner and keeping the tool dry will help maintain its appearance.

Ensure the knurled brass thumbscrew is tightened sufficiently to grip the sliding stock. If the threads are worn, contact the manufacturer for potential replacement parts or service.

Check that the spur(s) are sharp and clean. Ensure the sliding stock is moving smoothly and not binding. For mortise gauge use, verify both spurs are set to the exact same measurement.

For minor scuffs, a light sanding with fine-grit sandpaper followed by a wax polish may help. For significant damage, professional repair or replacement might be necessary.