Got chewed out by a 71 year old installer in Tulsa for power stretching a Berber, never made that mistake twice
He watched me fire up the power stretcher on a 40 oz Berber in a rental off Peoria and just shook his head, said 'you just voided that warranty and it'll ripple by spring.' He was right, three months later the seams waved like water, and now I stretch every Berber by hand no matter how much my back complains. Anyone else had a customer call back over a ripple you caused, or is that just me?
Waited three whole months for it to ripple? That old guy basically gave you a free countdown clock and it still came true right on time. Berber has that woven backing that fights back against the stretcher, so the tension has to work its way out somewhere and it always picks the seams. Hand stretching is brutal on the back but at least the seams stay put.