What is a contour gauge?

A contour gauge — also called a profile gauge or shape duplicator — is a measuring tool made up of a row of thin, sliding pins held in a body. Press the gauge against an object and the pins slide back, together taking on the shape of that object. You then transfer the captured contour onto the material you need to cut.

This solves a classic problem: a door casing, a heating pipe or a moulded skirting rarely has a straight profile, and copying that profile with a pencil and rule is close to impossible.

Application

Laying floors

The most common use. With laminate, LVT, vinyl, carpet or tiles, the gauge is used to mark the cut-out around a door casing, a pipe penetration or a chimney base.

Wall and ceiling finishes

When fitting plasterboard, matchboarding or plaster stop beads against an uneven wall or against old mouldings.

Restoration and moulding work

To capture an existing profile of a moulding, bead or reveal so that a new piece matches exactly. For genuinely precise copying of a profile, a cut-out counter-template in plywood or zinc is used alongside the gauge.

Plumbing

Cut-outs around pipes, radiator tails and wastes.

Versions and practical tips

• Width. Common sizes run from around 120 to 300 mm. For floor work 250 mm or wider is comfortable; narrow gauges have to be repositioned, and the join is where accuracy is lost.
• Pin thickness. Thin, closely spaced plastic pins give a finer contour; wide steel lamellae are sturdier but coarser.
• Locking. A gauge with a clamp screw or locking knob holds the contour while you trace it.
• Magnetic versions keep the lamellae in position and are useful on metalwork.

Method: press the gauge on square and with even pressure, check that every pin is genuinely bearing, trace the line, and then — for a cut-out that will disappear under a skirting or collar — cut one to two millimetres outside the line. A gap of a couple of millimetres almost always disappears under the trim, whereas material cut too generously cannot be put back.

Related terms

• Template
• Counter-template
• Skirting
• Moulding
• Bradawl

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