Are You Framing Your Windows in Zinc Correctly?
Zinc framing around a stained glass window should be part of the structural backbone of your window. But if you aren’t doing it properly, it could be the weakest link in your project.
What's the Difference?
The difference between framing your heavy windows properly or just adding the zinc came around the edge without much consideration for weight distribution, reflects itself in the longevity of your artwork. If not laid out properly on the corners, the weight of the window can be too much for the zinc to hold over time, and the result is that the zinc pulls away from the window.
If noticed in time, the window can be saved. But left unnoticed, the window could come crashing down to the floor.
A Visual Example of Poor Weight Distribution
Here’s a repair project that was brought to my studio that suffered from this exact problem.
Notice how the zinc pulled away from the window and bent? Luckily, the owners of the piece noticed it coming apart and were able to bring it down safely before it got any worse.
Always place the full length of zinc came from top to bottom along the left and right sides of a window. The top and bottom pieces should fit inside the vertical pieces of zinc where they are nestled in between these vertical pieces. The hooks would then be attached to the vertical pieces of zinc.
This allows the weight to be distributed along the full length of the sides instead of relying on a single joint at the top that cannot possible bear all of the weight.
The Size of the Came Matters
Another point to be made about using zinc, is to ensure that you’re using the right size of came for the size and placement of the window.
The window repair shown in the photo is 25 inches x 28 inches. That’s more than 4 square feet which makes for a heavy window! In my opinion, this should have been framed in ½ inch came.
Why? Well, two reasons really.
Did you notice how this window has huge hinge points? Both vertically and horizontally?
Although the horizontal hinge is separated by a small area of solid glass in the center, it is still super flexible in these areas because the hinge is so long and there's so much weight to the window. It needs much stronger reinforcement to prevent those seams from bending.
Not sure what a hinge point is? I wrote two articles on what hinge points are and how to reinforce them.
And the second reason is due to the sheer size of the window.
If ever you’re in doubt, just remember - the bigger the better when you need the came to help with some hefty reinforcement.
Quick question: do mitered corners make a difference in helping with strength? Or could I have been saving myself the effort of making perfect mitered corners all along by just using your format for the zinc?!?
Any work I do at the size of your example would only be done with lead came (along with cement) instead of copper foil…
Great questions Laurel. Mitered corners are preferred by many for their appearance. As long as you are hanging the panel from the side pieces of came and not from the one on top, then it will be just as strong as the diagram shown in the post. I stopped doing mitered corners years ago as I cut the zinc by hand and I struggled to get proper 45 degree angles. It was easier to cut them at 90 degrees, so I did! Plus, this way there is the open end of the came pointing down so water from cleaning the panel can drain completely. With mitered corners soldered all the way around, there’s no way for all the water to drain out properly. It’s not something I had thought of before doing 90 degree cuts, more of a discovery after the fact.
Why does my black patina lines turn white and faded. It makes my project look bad. What can I do to prevent that from happening?
Does this happen over time? If that’s the case, it’s likely from flux residue. The flux is acidic and needs to be cleaned with something that will neutralize it or this will happen time and time again. How are you cleaning your projects when you’re done making them? I used to use dish soap and baking soda mixed with water but had the white appearance show up anywhere from a week or two to a couple of months later. Now I always use NeutraClean and no longer have this issue.
Could u please help me out! I would like to know Y my stain glass panel separates after I have it all solder.
And also how can I tell if my iron is at the right temperature. I have it set on350 if I go higher it seems too hot
Enjoyed viewing ur site and as u see I am a newbee
Hello Melody, There are a number of reasons why a stained glass panel would separate after it’s been soldered. It could be poor foil adhesion, not enough solder, lack of reinforcement, poor design… the best way for me to help you is if you could please send me a clear photo with an example of this happening with one of your pieces. Send your email to firstname.lastname@example.org and I’d be happy to take a look. As for the iron temperature, as long as the solder is melting enough for you to apply it the way you want, there is no need to turn the temperature setting up. Temperature setting really only need to be changed based on climate, the type and brand of solder, as well as the application being used. As long as things are working for you, I wouldn’t change anything. 😉
Is there a way to remove a large solder splatter from a zinc frame?
Unfortunately, you’ll probably always have a mark. You can spread it around to make it more flat and less like a bump or, you could also try emery cloth (like sandpaper but for metal.) I would test the idea on a scrap piece of zinc first though to see if you like the results.
On large heavy windows, I thread twisted wire inside the zink and then twist the exposed ends into rings and solder. The window is then supported by the wire.
The top end of the vertical zink is not mitered leaving the end open for the wire to pass through. I fill in the gap with solder.
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Thanks for sharing that, Charles. It sounds like a great way to add even more support to the windows! (Also, the only way to get added to my email list is if you sign up for it. Your comments on the blog don’t automatically sign you up. )