As a welder, Lindsay Meikle remembers looking at a mistake on a drawing, not just a wrong welding symbol, but a larger error that reached the shop floor and, even worse, caused a larger structure not to fit. Rework ensued, either on the floor or (even more expensive) on the job site during erection.
Meikle chuckled quietly. “As a welder, I had the impression that steel detailing was really easy. I took all the good things they did for granted and blew the mistakes way out of proportion, thinking, ‘What were those guys thinking?’”
As a steel detailer at Victoria, British Columbia-based Exact Detailing, Meikle now knows just how much detailers juggle, from managing changeovers to writing RFI (request for information) after RFI to the engineer of record. That said, his years in the fab shop has made him aware of just how important the fabrication details are.
“With my years in welding, I can spot things that won’t work in fabrication, like weld access issues, as well as issues during the erection stage,” Meikle said.
He added that such issues often involve weld distortion, recalling a recent handrail job for a catwalk in an aircraft hangar. “We have a bunch of vertical pickets, all of them welded top and bottom. Several hundred of these welds would have been placed on the main top rail. I saw that and realized they’d get shrinkage if they put that many welds, so they’d lose a few mils on the overall length.”
The plan was to weld the handrail in the shop and then bolt everything in place on-site. Meikle knew that fastening bolt holes, especially those with threads, would be difficult if not impossible to locate accurately after the assembly had been welded in the shop. “So we decided to go with on-site welding rather than mechanical fasteners, just to nip that problem in the bud.”
Such a change goes against the common practice to minimize on-site welding in favor of mechanical fastening. On-site welding is expensive, but it’s less expensive than mechanical fastening followed by hours or even days of rework.
