Learning from mistakes in the fab shop

No one in a metal fabrication shop is perfect. Fabricators and welders shouldn’t be afraid to make fixable errors and then learn from them, writes Josh Welton. Getty Images

When I switched gears and moved from being a millwright at Chrysler to a driver/mechanic at General Dynamics, after what felt like a lifetime of learning, I reached a new frontier of my career.

As a millwright at Chrysler, I did a lot of rigging, crane operating, and gearbox and conveyor repairs. And I did quite a range of welding: tool room, repair, and general fabrication—mostly stick, a bit of MIG, and a bunch of TIG. We had saws, a basic hand-operated sheet metal brake, and an ironworker. That was about the extent of our metal shaping tools.

The fabrication shop at General Dynamics probably isn’t what you’d think of when you imagine a billion-dollar defense contractor’s prototype shop. We make a lot happen relative to the equipment that we have available to us. That being said, there were new things for me to figure out, the biggest being the hydraulic brake press. It’s one thing to put a 90-degree bend in a piece of sheet metal; it’s another to lay out multiple bends to tight tolerances in anything from ⅛-in. 6061 or 5052 aluminum to ½-in. RHA (rolled homogeneous armor) with complex cutouts and final shapes.

We usually have blueprints with the bend lines already laid out. All we really need to do is find the striking die with the corresponding diameter and set the brake’s depth gauge—in an ideal world, that is.

In reality, it's nice to have the ability to do the math manually to troubleshoot or double-check the layout. A lot goes into locating where to hit the metal with the die. There’s material length, the bend angle, and diameter, material thickness, material type, bend allowance, K-factor, and more to consider. Occasionally a flat piece will be cut to the wrong size, or the lines were calculated based on other erroneous inputs.

Even when every part size and number you’re given is perfect, there are plenty of opportunities to mess the thing up. It’s really easy to bend a part backward. The dies could be slightly off. The hit might not be exact. The springback is different depending on material type and thickness. And every time you massage the angle, there’s a chance you’ll strike in the wrong spot. Oftentimes, especially when working on one-offs, it’s more about massaging a less-than-perfect part into submission than getting it perfect on the first try.

All this is to say, I learned first by watching, then by doing. I’ve made a lot of mistakes, and I’ve learned from them.

Recently I was listening to a podcast about computer hackers when one of the guests mused that despite their parents having had more years with computers, they (the hackers) had a much deeper knowledge of computers than their moms and dads. They attributed much of this disparity to “button pushing.”

The older generation was intimidated by computers and computer science, afraid that they’d break something if they pushed the wrong button. The younger generation’s curiosity overrode any sense of trepidation. They gained awareness and intelligence by both succeeding and failing spectacularly while “button pushing.” In the short term, a hard drive crash sucks, but you’ve also learned one thing not to do the next time.

This brought me back to the fab shop. I once had a co-worker who was a bit older and had no desire to learn how to use the big brake press. I asked him why. And he said, “I’m afraid of screwing up the parts.”

“Dude, I mess up parts all the time! That’s how I learn!”

And we’re working with metal, so most of the time we can fix a bad bend. If not, we scrap it and try again. I tried to talk him into hopping on the press. No luck, though.

As for me, I’m still making mistakes and learning along the way.

Albert Einstein once said: “A person who never made a mistake never tried anything new.”