Below, I'm applying the copper foil to the mid-point of the side of a piece of glass. It takes some dexterity to do this but it gets easier over time.
One thing I've done is to insert "braided wire" into the potentially weak spots. The braided wire fits nicely and invisibly in between the pieces and serves to strengthen the overall piece. The second thing I will do is to add a light metal frame around the entire piece. It will not overpower the design but will ensure that the window will stay strong and sturdy for many many years to come.
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