Putting the Art back into Stained Glass.
Appreciating Stained Glass
What makes a good piece of stained glass?
How do design and construction work together? Or independently?
Where is the innovation in stained glass?
In this section lets look at the construction of stained glass in it basic forms, in order to learn how to separate quality from inferior work.
Not all glass is created equal. In ancient times there was no other means for making glass, other than by hand. It was full of impurities or contaminates which rendered it unique, hand working or tooling created irregularities on the surface or decoration as the workers became more adept at it. Nothing much changed for a very long time. A kiln to melt the ingredients, skilled workers to blow or spin glass into flat sheets.
These techniques are still in use creating the most expensive and beautiful glass, stained glass workers can buy today. Referred to as "antique glass" not because the glass is old, but because of how it is made, this glass is still made by hand. There are fewer and fewer of these glass manufacturers making glass in our world of every increasing fuel costs, required not only to melt the raw ingredients and safely cool the sheet glass, but also the shipping of materials to the factory and then the finished glass to the marketplace. As factories close, the skilled labour is lost. Less demand means cost cutting, discontinued colours or lines and eventual factory closings. Stained glass workers have seen huge increases in the cost of their most basic and beloved material glass.
There is also glass manufactured by highly mechanized factories. They too suffer from the same fuel cost issues, however their longevity is more secure because they can mass produce glass without the same kind of hands on labour costs. The glass that is mass produced and generally easily commercially available, is totally repeatable in color and consistent in thickness. It can also be textured. It is in no way inferior to antique glass as a piece of glass, in its ability to keep rain, wind and snow out, however antique glass has a decidedly evocative quality, clarity of color and internal radiance, that cannot be recreated by commercial manufactures try as they might, they cannot emulate it.
The middle ground of these two extremes, becomes a blending of hand made elements during the process that is still has highly mechanized. Usually smaller studios, specializing in a particular kind of glass, fill the need of niche markets.
antique glass is hand made, the most expensive, offering clarity of color and radiance. This glass will benefit from additional treatments like traditional
painting, enamel or silver stain. Flashed antique can also be acid etched.
commercially mass produced glass, least expensive glass, repeatable colours, readily available. Some glass is now being made compatible to facilitate fusing.
mid range niche glass manufacturers, definitely more expensive than mass production, production can be limited, not as easy to obtain. Some glass is compatible for fusing, others not. Successful traditional painting must be experimented.
There are two main methods of assembling glass, with a few innovations becoming more popular. Function and craftsmanship are very closely related and though not absolute their are some traditional views on assembly, that have stood the test of time.
The original method of assembly that allowed many individually pieces of coloured glass, to be assembled collectively. Lead cames create the matrix that surround each piece of glass and where the lead cames met or intersected each other, solder was applied to hold the joints together.
Lead cames come in a variety of widths and heights, profiles can vary, as can the strength of a came. Easy to cut, relatively easy to bend into the requirements of the matrix, weather durable, repairable, lead is, and has been, the matrix choice for hundreds of years.
The down side is that lead cames do contain lead. If handled carelessly, if proper precautions are not used doing specific aspects of construction, there is risk to the stained glass worker. These risks are reduced by proper personal safety equipment. Good practices now include recovery of lead cut offs for recycling and there are monitoring systems to ensure air/exhaust, leaving studios is clean of contaminates. These safety protocols do come with additional costs, that stained glass workers, as few as twenty years ago, did not incur.
Once the stained glass is finished and/or installed lead does not pose any risk of flaking or chipping, as does old paint, that contains lead. It is a material that certainly requires respect and responsibility. Where this responsibility has continued, is to the very manufacturers of the lead cames, becoming more environmentally conscious and responsible, as well.
Lead cames function best in flat planes. This makes the use of lead cames the best choice in windows that are architectural, meaning stained glass that is installed into an opening in a building. The lead cames can be further weather resistant by the addition of putty, filling in the space between the glass and lead came. External re-enforcements are easily attached to support larger panels.
Lead cames can be used for autonomous panels, for gently curved slopes, as in domes or skylights and has been used in the making of lamps. Lead is a heavy material and may deform without proper reinforcement.
Lead cames should be clean and shiny.
All joints should be soldered on both sides with sufficient solder so as to make where the joint was, undetectable.
The solder joints should be relatively equal in proportion and attractive.
There should be evidence that the window has been puttied.
Reinforcements should not detract from the overall design.
A rather modern technological variation of holding various pieces of glass together. Some say an innovation of Louis Comfort Tiffany, primarily to utilize the cut offs from his large window commissions. This pieces were then cut smaller to accommodate curvatures, which then became the famous Tiffany lampshades.
Usually small pieces of glass wrapped around the perimeter with a copper foil, then soldered in its entirely, front and back. The solder binding to the copper foil only, creates the matrix that holds everything together. The soldering should appear neat and smooth with a generous enough amount of solder to be sufficient matrix.
Copperfoil does not require putty/weather resisting because the foil adheres to the glass, without a gap. However copperfoil is not suitable for architectural applications. The adhesive does dry out allowing for water penetration.
Copperfoil also comes in various widths to accommodate a variety of glass thicknesses and gives the artist freedom to create various looking thicknesses of line. The copperfoil comes in various backings, so that when used with clear glasses, that the foil can be matched to the desired finish silver, if the solder is left natural, black, if the solder is darkened, or copper if a coppering agent is used. Copperfoil should be fixed neatly and evenly so no undo amount of backing is showing.
Copperfoil has many applications it can be used in autonomous panels, it can be re-inforced for larger works, but must be protected from the elements. Copperfoil is best used for three dimensional work, especially in lampshade making.
There is still some risk to the stained glass worker as the solder has lead in it. With copperfoil, requiring so much solder to create the matrix, the risk is not insignificant. There are new lead free products being attempted, but as of yet, the stained glass industry still prefers the the freedom and reliability of lead based solder.
Neat and even application of copperfoil to the glass edge.
Appropriate use of coloured foil backing.
Neat and smooth soldering.
Evenness of line is desired, but not necessary when used artistically.
Enough solder to create sufficient matrix strength.
Can be re-enforced internally thus invisibly.
Solder left natural or coloured, should be clean and shiny.
Fusing Slumping Warm glass:
Stained glass fusing/slumping is a relatively new innovation. Fusing and slumping eliminates the technical skill of mastering either matrix. It has already gone through it's tough initiation into the stained glass fold, because of a few pioneers who demanded more from stained glass. Not wanting to be confined by the matrix of either lead or copperfoil, fused glass is free from these constraints, allowing for easy layering of color and shape. Fusing glasses together could add detail to otherwise too difficult or ungainly traditional matrix methods and as the medium launched into its own full expression, entire surfaces were fused.
A couple of things had to occur for it to have taken off, as it has.
First the cost of kilns had to come down and with that, all the new gadgetry to make them cost effective to use. A wide variety of sizes are available, such as front load or top load models, single shelf or multiple shelves to maximize the heating chamber, depending on the artists requirements. Kiln companies have done a great deal of educating about their products and have offered many courses to help generate interest.
The second big innovation is within the glass manufacturers realm of glass chemistry. Prior to about twenty years ago, glass recipes were unique to the color. The chemical mix had it's own unique rate of expansion and contraction. If you tried to fuse or slump incompatible glass, that is, glass whose chemistry was different enough to expand and contract differently, the project was doomed to failure by cracking or worse, exploding in the kiln. Many of the large stained glass manufacturers, seeing the potential for fusing and slumping, have created product lines of glass that are now fully compatible within that product line. This has created much more safety and reliability.
The down side of any fused or slumped glass, is that once it does crack or break, the piece in its entirety is thrown away and replaced. At the present there are no techniques to restore or repair this kind of work. The technical skill is assembling the various pieces of glass and controlling the kiln.
Fusing can be incorporated into stained glass or stand alone.
Colors should be shiny and bright.
I hope everyone can start to use this information with their local art groups - opening dialogue to create better understanding of what is involved in making good stained glass. And I appreciate it has been generalized, so if you feel I've missed something important that should be addressed, let me know.