Stained Glass/construction and reinforcement
QUESTION: Predesign phase for a 24 x 80 vertical window with exterior clear glass: I can foil it or lead it, but it's an organic design, so I'm thinking a combination maybe? or just foil. I've never made anything in sections before, can this be done in one piece utilizing restrip? Also, the framing is aluminum, so this is what steers me away from total lead - how would I set a rebar in a metal frame? All suggestions welcome! Thanks.
ANSWER: Great task you have ahead of you, Jay.
By it nature copper foil is stronger than lead. That is why Mr. Tiffany invented the method.
1) The piece can be strengthen internal with a copper coated steel ribbon (hard to find but is available) Contact me if you cannot find it. This thin steel is placed between the pieces (it bends to the shape of the glass) and solder over so it is not visible. It can be added in strategic areas and even doubled. The ribbon will bend one way but is extremely rigid when on its side.
2)The copper coated steel ribbon can also be place inside the outside U shaped zinc channel. And an H zinc is appropriate for the outside edge and adds more strength. A wood frame will also add strength if that can be worked into the project. And outside zinc channel that is even 1 inch wide will bend. And the finished piece will be stronger when it is installed and totally vertical. But do not lean it.
3) I also combine copper foil with zinc to add speed and strength. I do not usually use lead as it is weak and easily bends.
4) You might consider doing the piece in 2 or 3 sections. It might not be what you want, but would definitely be stronger, easier to transport, easier to install and last but not lease it would be easier to repair if that is ever required.
5) And remember you can use a wider copper foil to get a wider and stronger joining.
6) And last but not least you can put re-bar on the outside in several places for added strength. The re-bar can be bent to flow with the pattern seams and it becomes less visible than just running from top to bottom or side to side across the open glass areas.
Wishing you lots of luck and let me know need clarification about any part of this answer.
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QUESTION: Much appreciation for your prompt response! Of course, there are new questions. I'll ask in order.
1. I assume you refer to Morton strongline. How is it different from copper restrip?
2. What dictates the framing decision to choose between h zinc or u zinc? Because the window is metal framed, I assume I should use metal stops and trim, not wood. Am I wrong?
3. What would be the zinc sizing and profiles when stacking panels? How do you secure them before the trim goes in place?
4. Can you even do rebar when using a metal trim? How to notch?
I will try to answer as best I can.
1) Morton strongline is exactly what I am using but my source is generic. But I am pleased that Morton has it in their product line. In the past it was very had to run down.
2) I use H zinc when the piece get bigger than about 18x24. I would say that I put a wood frame around any piece that I can. If it is hanging on its own the glass needs the extra support. Zinc of any size is simply not strong enough to support a larger piece of stained glass that is free hanging.
I always add zine to edge and then add the wood frame.
If the piece is being installed in a existing window frame, whether it is wood or metal, the stained glass should still have a zinc or lead edge to protect that edge while being transported and installed. The stained glass is now being supported by the existing window and is not using the edge for support. (just protection of bumps)
If I am manufacturing in one place and installing in another I usually add an H lead to the outside so if for some reason it does not fit I can take a knife and trim the outside of the H lead if needed. This is especially important on a dome shaped window. It is very had to get the dome shaped exactly.
I am not for sure what you are asking but hopefully I have covered your answer. If not get back to me.
3) Every install will be unique and you will have to work with what you have presented to you.
If I am doing separate panel I have the window frame build so that it has the number of separations need for the glass. So each section has its own edge and is installed in an opening designed for that section piece. It would be extremely difficult to install each piece of glass on top of each other so that it is in one piece with only a zinc trim between. Think of the doors that have many panel opening. You can have one piece of stained glass so that the pattern runs through all the panels as one design but it is supported by all the separate openings. You could have a different install if the design is horizontal 80x24. Now the sections are not add weight as the window goes up and is better supported. It would now be possible to do the window in one piece with very careful transportation and installation. And if done in separate pieces could possibly be added in place with wide H zinc. But if it is an outside window you will need to put in your glazing in place to prevent the air exchange. Lots to think about, yes!
4) You can do external rebar by attaching the rebar at any point it touches or passes over the edge of the zinc/lead edge or the solder joints. I have had, at time, do a cap on the rebar because it would not bond with the zing trim. That can be some of your "strongline" around the rebar and that will bond to zinc/solder seam sometime better that the rebar to the zinc.
And, lots of luck and let me know how it went and what you decided to do.