`Charles Street MBTA station welding specifications case`

Architectural welding firm consulting Tom on welding to unspecified 1910-era steel during MBTA station rehab. Tom looks up the procedure in Stout and Doty in five minutes for $500. Used to illustrate the practical value of weldability tables.

Remember the little video we did, a finite element analysis on the hydrogen in two different thicknesses of steel, quarter-inch and inch, preheated and non-preheated, and how fast the hydrogen diffuses through when you weld on it? You go back and watch that — you'll find this is basically a 1940s table version of what to do. So I'd look up the steel, ask what's the thickness and the chemical composition. There's a firm out here that does a lot of architectural work. They were working on the Charles Street MBTA station, built in 1910. Didn't even have steel specifications back then for some of the steels they were using, but they had to weld to them when rebuilding. For 500 bucks, I would write them a welding procedure if they told me the chemical composition and the thickness. I would go to this book — I even told them this much, but they never wanted to learn how to do it. They wanted to pay me the 500 bucks. It took me five minutes. $500 for five minutes' work. It tells me what preheat should be, if you need a postweld heat treatment, and whether you need to peen it — hammer the surface to relieve residual stresses. Postweld heat treatment would be a stress-relief heat treatment. Lots of different welding procedures, right there in Stout and Doty.