Hey, so I've got about 150 units, more than half of which have been in service for 21 years. They all are equipped with cast steel "Altman" or "Colortran" C-clamps. They're in use year round, 8 shows a week every week except for about 9 weeks of changeover over each year. We do 6 changeovers a year and at least half of the units get re-hung each changeover. What I'm getting at is that these clamps have been under tension for 21 years and flexed a lot of times. I've only seen a C-clamp break once - I was young and strong and trying to do a weird focus and got overzealous tightening it down. Clamp busted at the top bend of the "C" and the unit ended up hanging by the safety cable. That said, I find myself wondering, in a preventative maintenence state of mind, whether anybody has any experience with these reaching a point where the metal gets fatigued and clamps start breaking without any provocation. Last thing I want to see is a chunk of clamp hitting the deck in the middle of a show, actors and audience stop paying attention to the story and thinking about their lawyer's phone number instead.... Anything anybody can offer here?