hi Tin
The gauge you're looking for is a modified Starrett #22C gauge that's specially built for the place you work. They cost about $220 - 240 depending on the order. If you call Starrett and ask, they should be able to accommodate you. As you can see, they're expensive. Starrett probably doesn't know them by the name you called them. To them it's just a custom weld guage.
By the way, you really should call Rick where you work at extension 2675 or
2143 and introduce yourself. He's got a manual that shows how the tool is supposed to be used. He'll be a good guy to answer your questions. I don't mind at all when I get a call from a shop welder. I teach the metallurgy and welding technology classes at our place for our design and steel trades apprentices and make sure my students know how to reach me. I'd rather have somebody ask the question than have to fix a mistake later. Rick will tell you where I work.Meanwhile, I've taken pictures of the gauge we use. It's a sliding scale weld gauge that's made by Action Tool Services in Hampton VA. (Their ATS B0440. I don't know how much they cost. They'll probably cost less if you order a bunch. The biggest order he ever filled was for 50 pcs.) I just don't know where to put the pictures so that other people can see.
I've also got a cartoon of the Starrett gauge.
And I bet the rest of the readers of this N.G. are looking at us like we're nuts. These are precision gauges. And they're used to measure (sometimes) pretty big fillets. But customers don't have the tools to evaluate whether or not a slightly undersized weld will or will not be OK for the life of the product. No one wants to pay for a new analysis just because the fabricator missed a few fillet sizes. The design document is what's required and departures aren't treated casually, so all disclosed errors are treated as defects and repair is mandatory. The costs for correcting undersized welds become greater the later in construction these deficiencies are discovered. It's one thing to make an occasional correction early, especially by the welder responsible for the work, but after a touchy product is painted, and sometimes moved to its next construction point it becomes more difficult and expensive to fix. Piping systems need to be broken down and re-hydro tested. Liquid penetrant tests need to be re-done. Some mag particle tests are done after many days delay to reduce the potential for undetected delayed cracking. All are penalties for late detected undersized welds. The careless fabricator leaves himself open for trouble when an owners agent with time to spare, inspects a final painted, clean, well lit structure. Accurate tools help. Using them helps even more.
Some large fabricators have measuring devices built into their robotic work cells. Our government funded the modification of one of these tools into a hand held model that can be used to scan and validate structural welds. Several shipyards have tested it. I'm not sure where the program is just now. I'm thinking it's still a bit pricey and klugy for convenient use.
This N.G. is a great resource. Lots of people read and appreciate it. Thanks to all the regular posters who do a great job in keeping interest in the craft.
Sincerely j
PS. If somebody has someplace for me to put those images, let me know.