Harder Stone, Same Workshop

The symptoms point to using soapstone habits on a harder, more abrasive stone. Soapstone is soft and can be undercut with light pressure and thin edges. Chlorite is harder and more brittle; a thin edge digs in, lever forces build up, and the stone chips along the cut. The grinder glazes the surface because too much pressure and speed generate heat, which can also alter the stone's surface and blunt the abrasive.

Changes:

• Replace light soapstone chisels with heavier carbide-tipped or harder steel chisels suited to the stone. Keep edges sharp and use a wooden mallet of appropriate weight.
• Work in shallow passes. Remove bulk from the centre of the relief outward, never lever against a thin undercut edge. Support the block firmly and carve with the grain where possible.
• Use the grinder at lower speed with light, sweeping passes, or switch to a wet method. Do not hold it in one spot. Dress the wheel and check for loading.
• Cut a test relief on a waste offcut from the same block before touching the panel. Adjust mallet weight and pass depth from that test.
• Leave a stronger margin around deep undercuts and finish edges with hand tools rather than the grinder.

The aim is not simply 'work slower' but to match tool mass, edge angle and pass depth to the stone. If the workshop cannot obtain suitable tools quickly, it should reduce relief depth on the remaining panels rather than risk further chipping.

Dry grinding and chiselling of stone produce respirable crystalline silica dust, which is a serious lung hazard. The cough must not be dismissed as ordinary irritation.

Immediate controls:

1. Stop dry grinding indoors. Move cutting and grinding outdoors or to a well-ventilated area, and use water suppression or a wet grinder where possible.
2. Provide properly fitted respirators-at least an N95 or P2, ideally a half-face respirator with particulate filters-and train carvers to fit and maintain them. A cloth or surgical mask is not adequate.
3. Use eye protection, hearing protection and sturdy footwear. Keep the floor wet or damp-swept; never dry-sweep dust.
4. Separate the dusty area from eating and drinking. Provide washing water and change clothing before leaving.
5. Arrange a medical check for the carver with the persistent cough; he should not continue dry grinding until assessed. Record the incident.
6. Check the electrical grinder and cable; an overheated tool is also a fire and shock risk.

A dust-extraction unit and local exhaust ventilation should be budgeted before the next contract. The workshop should also tell the contractor that safe working conditions may affect output; this is a legitimate production constraint, not an excuse.

First assess the crack properly. A hairline along a bedding plane may be a natural weakness that opens during carving, or it may be superficial. Tap the block and inspect the crack under raking light; mark its extent. Do not fill a structural crack with adhesive and present it as sound.

Decision rules:

• If the crack crosses the central relief area, reject that block for a deep-relief panel. Use it for a shallow-relief or background panel, or for a smaller product, and inform the contractor.
• If the crack is near an edge, redesign the panel so that the affected area becomes a border or is cut away.
• Do not start deep undercutting across the crack line.

Because the contractor accepts fewer panels, offer six high-quality panels instead of eight, with the cracked block used only for a non-structural item or replaced. Put the reduced quantity, revised price and delivery date in writing. Six good panels protect the workshop's reputation better than eight with one visible failure. Use the remaining two weeks for controlled production, not for rushing the crack block. If the contractor wants all eight, the only honest options are a replacement block or a longer deadline-not hiding the defect.