Thought my tube roller was fine until a 20 year guy in Gary asked why my welds kept cracking
So I have been running the same roller setup for about 3 years and I kept getting these hairline cracks right at the seam after about 6 months in service. I figured it was just heat input or bad filler so I changed rod, played with amps, even preheated, nothing worked. A 20 year hand from the Gary, Indiana local was walking through our bay for a job and he watched me roll a 36 inch can for like two minutes and goes "your rolls are crowned, that thing is pushing the plate thin in the middle." I put a straight edge on the rolls and sure enough there was .030 of wear in the center so I was thinning the shell without even seeing it. Swapped rolls and the last four cans I fit up came out dead straight, zero cracks in the test coupons. Feels dumb that I chased welding for months when the problem was upstream the whole time.