What is a cape chisel?
A cape chisel is a cold chisel with a notably narrow cutting edge, used to cut a narrow groove — a chase — in masonry, stone or metal. Where an ordinary cold chisel has an edge of twenty to thirty millimetres, a cape chisel’s is usually no wider than about ten. All the striking force is therefore concentrated on a small area, and the chisel penetrates more readily. In Dutch this tool is called a ritsbeitel.
Characteristics
- Material — typically chrome-vanadium or tool steel, with a hardened and ground cutting edge.
- Striking head — deliberately left slightly softer than the edge so it deforms under the hammer rather than shattering.
- Length — commonly between about 150 and 300 mm; longer means more distance between hammer and hand.
- Shank — plain, knurled or shaped for grip. Versions with a rubber hand guard damp the vibration and protect the hand from a missed blow.
What you use it for
- Marking out and opening chases in plaster or soft masonry, for an electrical or water run.
- Raking out joints where pointing has to be replaced — although larger areas go faster with a mortar raking disc.
- Cutting grooves and keyways in metal, the tool’s original metalworking job.
- Setting a break line in a stone or tile so it can then be snapped.
Working safely and cleanly
- Always wear eye protection. Hardened steel and stone throw sharp splinters; this is not a tool to use without goggles.
- Work from the edges inwards. Score the edges of the chase with shallow blows first, then remove the middle. That stops the plaster tearing out beyond your line.
- Grind off any mushroomed head. Once the striking head spreads into sharp burrs they must be ground away: those burrs can fly off under a blow.
- Keep it cool while grinding. Steel that turns blue has been tempered and has lost its hardness.
- Check for services first. Never chase blind into a wall; use a detector, and stay out of structural elements and lintels.
Related terms
- Cold chisel
- Chisel
- Plaster coat
- Lintel
- Masonry
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