How Much Lead Came Do You Need for Stained Glass?
Calculating the total length of lead came ahead of time helps you avoid running out of material mid-project. Lead came generally comes in two types: border pieces use thick 8-10mm U-shaped came for strength around the outer edge, while the boundaries between interior glass pieces use thinner 6mm H-shaped came. The border amount is simple to estimate — it's just the perimeter of the piece, or (width + height) x 2.
The interior lead amount depends heavily on design complexity. A simple geometric pattern with 5-10 pieces needs interior came of roughly 1.5 times the perimeter length, but a detailed design with 25+ pieces can need 4 times the perimeter or more, since the total boundary length between pieces grows dramatically as piece count rises. If you're a beginner, designing with fewer pieces keeps both material cost and build difficulty lower.
When you actually shop, buying about 10% more than the calculated amount is a safe margin. Bending came around curves creates cutting waste, and joints between pieces consume a bit more length than expected. Designs with lots of curves in particular deserve a more generous buffer.
Frequently Asked Questions
Yes. The border (outer edge) needs strength, so it typically uses thick 8-10mm U-shaped came, while the boundaries between interior pieces use thinner 6mm H-shaped came.
Yes. As piece count grows, the total length of boundaries between pieces increases dramatically, so a complex design can need 2-3 times more lead came than a simple one.
Buy about 10% more than the calculated amount to account for cutting waste and losses at joints.