I restore old pieces of stained glass for clients. These have been everything from 1930’s front door panels to delicate panels of hand painted pieces from old furniture, replicating broken glass panels from Arts and Crafts cupboards, and replacing broken panes in windows.
This usually means taking the whole piece apart and re building it with new lead, and re-cementing the glass into the lead.
Once lead gets old, it becomes brittle and very difficult to work with. Restoration is more involved than it seems, it takes time to match antique glass and involves research and leg work finding it.
But, very rewarding when you see a beautiful old window brought back to life.