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The Timeless Strength of Leading Came
The leading came technique is the elder statesman of stained glass assembly. Its history stretches back over a thousand years, evident in the breathtaking windows of medieval cathedrals across Europe. This method relies on H-shaped or U-shaped strips of lead, called ‘came’, which have channels on one or both sides to hold the glass edges. Think of it like a miniature metal framework built piece by piece.The Leading Process Unveiled
Assembly begins with a precise pattern, known as a cartoon. Glass pieces are cut carefully to match the pattern sections, leaving a small gap to accommodate the ‘heart’ or central web of the lead came. Before use, the lead came, which typically comes on spools or in strips, often needs stretching. Stretching straightens the came and slightly work-hardens it, making it firmer and easier to handle. The artisan starts by framing one or two edges of the panel with a border came, often a U-channel for the outside edge. Then, using a specialized tool like a lead knife or lead dykes, they cut lengths of H-channel came to fit between adjacent glass pieces. Each piece of glass is carefully slotted into the channel of the adjoining came. The process continues methodically, building the design piece by piece across the workbench, often using horseshoe nails or layout blocks to hold the assembling panel securely in place. Once all glass pieces are encased in their lead channels, the crucial step of soldering occurs. Every point where lead cames meet (the joints) must be soldered on both sides of the panel. A flux is applied to clean the lead and help the solder flow smoothly, creating a strong, weather-resistant bond. Traditionally, a 60/40 or 50/50 tin/lead solder is used, melted with a soldering iron. After soldering, cementing is essential for traditional leaded panels, especially those intended for windows. A special waterproofing putty or cement is forced into the gaps between the glass and the lead flanges on both sides. This adds significant strength, rigidity, and weather resistance to the panel, preventing rattling and drafts. Excess cement is cleaned off, often with whiting powder, leaving neat, defined lead lines.Characteristics of Leaded Glass
Leaded stained glass possesses a distinct, bold aesthetic. The lead lines themselves are a prominent design element, typically thicker and more uniform than copper foil lines. This method excels at creating geometric patterns, straight lines, and larger, less intricate designs. Its inherent strength, particularly after cementing, makes it the preferred choice for architectural installations like windows and doors that need to withstand environmental stresses. The weight is considerable, however, and structural support like saddle bars might be needed for very large panels.The Intricate Detail of Copper Foil
Developed and popularized by Louis Comfort Tiffany and his studios in the late 19th century, the copper foil technique revolutionized stained glass design. It allowed for much finer detail, tighter curves, and more complex, three-dimensional shapes than were easily achievable with lead came. This is the technique behind the iconic Tiffany lampshades.The Copper Foil Process Explained
Like leading, the copper foil method starts with precisely cut glass pieces based on a pattern. However, instead of fitting into lead channels, the edges of each glass piece are meticulously wrapped with thin, adhesive-backed copper foil tape. The foil typically extends slightly over the front and back surfaces of the glass edge. Applying the foil requires care. It must adhere smoothly without wrinkles or gaps, and the overlap onto the glass faces should be consistent. Once wrapped, the foil is burnished firmly against the glass using a tool called a fid or burnisher. This ensures excellent adhesion and creates a tight seal, which is critical for the next step. The foiled glass pieces are then arranged according to the pattern, fitting snugly against each other. Flux is applied over all the copper foil lines. Using a soldering iron and solder (often 60/40 or 50/50 tin/lead), the artisan then flows a bead of solder over the entire foiled seam. The solder adheres only to the copper foil, effectively ‘tinning’ the foil and joining the adjacent pieces together. This creates a continuous metal seam holding the glass together. Unlike leading, there’s no separate cementing process. The soldered seams provide both the structural integrity and the finished look. After soldering both sides, the panel is cleaned thoroughly to remove flux residue, which can be corrosive over time. A patina can be applied to the solder lines to change their colour from silver to copper or black, enhancing the overall design.Safety First! Both lead came and copper foil techniques involve working with lead (in the came or solder) and potentially sharp glass edges. Always work in a well-ventilated area, wear safety glasses, and consider using protective gloves. Thorough hand washing after handling lead materials is essential to prevent ingestion.
Characteristics of Copper Foil Glass
Copper foil allows for exceptionally detailed and intricate designs. Because the foil can follow tight curves and sharp points easily, this method is ideal for organic shapes, floral patterns, pictorial scenes, and complex lampshades. The resulting solder lines are generally finer and can vary in thickness more than lead lines, offering a different visual texture. While strong, foiled panels are typically less rigid than cemented leaded panels of the same size and might not be the first choice for large, exposed architectural windows without additional reinforcement. They are, however, perfect for suncatchers, decorative panels, lamps, and intricate inserts.Choosing Your Method: Lead vs. Foil
The choice between leading came and copper foil often depends on several factors:- Design Complexity: For intricate details, tight curves, and organic shapes, copper foil is generally superior. For bold geometric patterns, straight lines, and a traditional look, lead came excels.
- Desired Aesthetic: Do you want prominent, uniform lines (lead) or finer, more variable lines (foil)? The lines themselves are part of the art.
- Structural Needs: For large panels or external windows requiring maximum strength and weatherproofing, cemented lead came is the traditional and often better choice. Foil is suitable for smaller or internal pieces, or items like lampshades.
- Project Type: Lampshades and 3D objects almost exclusively use copper foil due to its flexibility in forming shapes. Traditional windows favour lead. Decorative panels can use either, depending on the desired style.
- Skill and Tools: While both require skill, some find foiling intricate curves easier than precisely cutting and fitting lead came around them. The toolsets are also slightly different (lead knife/dykes vs. foil shears/burnisher).
Verified Fact: The copper foil technique, often called the “Tiffany Method,” was developed within the Tiffany Studios around the 1880s. It enabled the creation of their famous lampshades with their complex, nature-inspired designs, something very difficult to achieve with traditional lead came alone. This innovation significantly expanded the artistic possibilities of stained glass.Ultimately, both leading came and copper foil are venerable and valuable techniques in the stained glass artist’s toolkit. Many artists become proficient in both, selecting the method best suited to bring their unique vision to light. Understanding the process, strengths, and visual characteristics of each allows for a deeper appreciation of the craftsmanship involved in every stunning piece of stained glass, whether it’s a centuries-old cathedral window or a contemporary foiled suncatcher.
