How long an epoxy glue joint should be left in the clamps is very dependent on how much stress the joint will be under. A general guideline is that low-medium stress joints can be un-clamped after an overnight cure. A high stress joint like a large bent lamination should be allowed a full cure (72 hours) before unclamping.
Our Quick Cure Adhesives are an exception to the above guideline. In room temperature conditions they will develop 90% of their strength after curing for 1 hour.