My seam roller snapped clean in half on a Friday afternoon job in Tempe. The handle just sheared off.
It was a Roberts 10-550, about 8 years old. I was putting pressure on a tricky seam in a sunken living room and crack. Had to finish the last 400 square feet by hand with a leftover piece of carpet pad. Took an extra two hours. What's a heavy duty roller you guys actually trust for thick commercial glue down? I'm done with this one.
My buddy had his Crain 619 give out on a hotel ballroom job last year. The steel shaft actually bent under the roller head, just from working a stiff-backed carpet. He swears by the heavier Crain 624 now for anything serious.