Stained Glass Solder Weight Calculator
Calculate the amount of solder needed for a stained glass project based on panel size, seam length, and technique.
Estimating solder consumption for stained glass projects is essential for budgeting and purchasing. The amount of solder needed depends on the total seam length, the soldering technique (copper foil vs lead came), the width of the foil or came, and whether you create flat seams or raised beads.
Solder Consumption Formula
Solder Weight (g) = Total Seam Length (cm) × Consumption Rate (g/cm) × Technique Factor
Consumption Rates by Technique
| Technique | Consumption Rate | Description |
|---|---|---|
| Copper foil — flat seam | 0.35 g/cm | Thin, flat solder line |
| Copper foil — beaded seam | 0.55 g/cm | Rounded, raised solder bead |
| Copper foil — heavy bead | 0.75 g/cm | Thick decorative bead |
| Lead came — tinning joints | 0.20 g/cm of joint | Small solder points at intersections |
For copper foil, total seam length is the sum of all foiled edges where pieces meet. For lead came, solder is only applied at joints (intersections), not along the entire seam.
Estimating Seam Length
For typical stained glass panels, the total seam length can be estimated from the number of pieces:
Estimated Seam Length (cm) = Number of Pieces × Average Piece Perimeter / 2
The division by 2 accounts for each seam being shared by two adjacent pieces.
For a rough rule of thumb: Seam Length ≈ Panel Area (cm²) × Piece Density Factor
| Design Complexity | Pieces per 100 cm² | Density Factor |
|---|---|---|
| Simple (few large pieces) | 1–2 | 0.5 |
| Moderate | 3–5 | 0.8 |
| Complex (many small pieces) | 6–10 | 1.2 |
| Highly detailed | 10+ | 1.6 |
Worked Example
A 30 × 40 cm copper foil panel with 35 pieces, moderate complexity, beaded seams:
Panel area = 30 × 40 = 1,200 cm² Estimated seam length = 1200 × 0.8 = 960 cm Solder weight = 960 × 0.55 = 528 g
Both sides need soldering, but the second side uses less (about 60% of the first side): Total = 528 + (528 × 0.6) = 528 + 317 = 845 g → buy 1 lb (454 g) spool plus extra
Solder Types for Stained Glass
| Solder | Composition | Melting Range | Best For |
|---|---|---|---|
| 60/40 | 60% tin, 40% lead | 183–190°C | General copper foil work |
| 50/50 | 50% tin, 50% lead | 183–216°C | Lead came work |
| 63/37 | 63% tin, 37% lead | 183°C (eutectic) | Smooth, shiny joints |
| Lead-free | 96.5% tin, 3.5% silver | 221°C | Food-safe items, higher cost |
Waste Factor
Add 10–15% to your calculated amount for waste — drips, practice, and rework. Beginners should add 20–25% as they learn to control solder flow.