Tools you might need next
Calculate glaze batch weight from unity formula and raw material analysis. Scale recipes to any batch size for consistent studio pottery glazing.
Create kiln firing schedules with ramp rates, hold times, and cone temperatures. Plan bisque and glaze firings for electric and gas pottery kilns.
Calculate clay shrinkage percentage from wet, dry, and fired dimensions. Plan pottery sizes accurately for clay bodies from leather-hard through glaze firing.
A coil wrapped around a mandrel or stone uses length equal to the number of turns times the circumference at that diameter, plus end tails.
Wire length = N × π × diameter + tail allowanceEach complete wrap around a cabochon follows an elliptical or circular path. Measure girdle circumference and multiply by number of passes, adding 20–30 mm for binding wires.
Length ≈ wraps × girdle circumference + crossover allowanceA bezel strip encircles the stone girdle. Add metal thickness correction and 1–2 mm overlap for the solder seam.
Bezel length = π × (stone diameter + metal thickness) + seam overlapUpdated: July 2026
Five coils on a 17 mm mandrel with 50 mm tails each end: 5 × π × 17 + 100 ≈ 367 mm of 20 ga wire. Add 10% for spiral spacing if coils are separated.
20 × 15 mm oval cab with girdle ~52 mm. Four horizontal wraps plus two vertical weaves: (4 × 52) + (2 × 30) + 40 mm binding ≈ 348 mm of 22 ga square wire.
8 mm round stone, 0.5 mm bezel wall: strip length = π × (8 + 0.5) + 1.5 mm overlap ≈ 28.2 mm of fine silver bezel strip.
Wire follows curves, not straight lines. Use actual wrap circumference and count every pass including under-stone binding wires.
Always add 10–15% extra for filing, re-bends, and mistakes. Precious metal scraps can be refined; splicing mid-wrap looks unprofessional.
Running short on wire mid-project wastes time and creates mismatched metal color from splicing. This calculator estimates wire length for coils, basket-weave wraps, bezels, and ring shanks from dimensions and wrap count.