April 24, 2014
It’s something welders hear all the time: “It’s a small job, just a quick fix,” meaning you’ll charge little if anything. It’s not that simple, not by a longshot.
A buddy has a “5-minute” weld job for you. Or a customer calls needing a quick fix; you know, “it’s just a small crack” or “it’s only a pinhole.” Worse yet, maybe he or she already tried to repair it and it didn’t hold up. If you weld, you’ve certainly been there. This post is for all you welders, something to share with your friends and clients to help them understand why it’s going to cost them more than a 6-pack for your help on their easy fix. Here are three of the more common “quickies” I run into.
1. The "5-minute job" myth.
Phone rings: “Hey, man, got a quick job for you, will only take 5 minutes. Can you help me out?”
There is no such thing as a 5-minute job. That’s code for “it looks simple to me, so you won’t charge me much/anything to do it, right?” Here’s the deal: Nine times out of 10, there’s more to a weld repair than meets the eye, and even on the 10th time, it’s never as easy as just laying a bead.
Say a tab breaks off of your 5.0 Mustang®’s intake (Figures 1and 2)… it just needs welded back on. It was a clean fracture.
Most nonwelders will look at the tab, hold it back up to where it came from, and think it just needs a pretty weld all the way around the outside edge to keep it in place. The reality is you won’t get enough penetration by doing that.
You need to V out the tab and/or head so you get 100 percent penetration. Now, you also have to deal with keeping the tab located properly, which is problematic. What looks like a quick fix to the layman actually is a pretty involved repair process.
2. “It’s just a pinhole” usually is not just a pinhole.
Whether it’s an aluminum fuel tank off of a MotoGP™ bike, or a steel tank off an old Harley, it’s typically not as easy as just firing up the TIG torch and dipping in some filler to repair the pinhole.
Aluminum is such a fickle material. I hate quoting aluminum repairs. Even virgin aluminum can be problematic, but now with a tank you’re dealing with a piece that’s served its entire life as a vessel. Aluminum is so porous that it just absorbs contaminants, so whether it’s been an oil receptacle, a fuel cell, or a water tank, it has junk embedded within its walls. A thorough (and often time-consuming) cleaning needs to happen before you strike an arc, and even then, there’s only so much you can do.
Recently I had a friend call me up about fixing a pinhole in an aluminum fuel tank (Figures 3 – 7). He thought I’d just be able to quickly fill in the hole and that would be that. Before even looking at it I knew it would be more involved (based on what I wrote above), but once I saw it, there were even more complications. There was a pinhole, but it wasn’t in the original material, it was in an old repair. The previous “welder” hadn’t been able to clean the compromised area well enough to lay down a proper weld, so there was just a blob of bubble gum-looking metal sanded down flush with the outside of the tank. Now, rather than the “quick fill” of a pinhole, I needed to cut out a 2-in. by 2-in. section of the tank and replace it.
When working with steel, I learned early on that pinholes usually are a sign of something much more ominous. I remember sitting in a welding course at the Chrysler/UAW tech center when a co-worker brought in an old motorcycle tank he’d been messing with. Every time he tried to fill in a pinhole, the material would vaporize in front of him. One of the instructors came up and told him he was wasting his time: “You need to cut the entire bottom out of that tank and replace it.”
You may think there’s just a small pinhole in that piece, but it’s really just the first place the rust has eaten through. Chances are, if you cut into the tank you’ll find the material isn’t too far away from becoming Swiss cheese.
A close relative to “just a pinhole” is “just a small exhaust leak.” Like the pinhole in a steel gas tank, a small leak in your rusted-out exhaust means that you’ve got corrosion issues. Plugging it up with MIG wire won’t cut it; at the very least you probably need a decent chunk of the tubing replaced.
3. “Can't you just weld over the crack?”
No. Whether it’s a busted motorcycle seat bracket (Figures 8 and 9) or some other bracket (Figures 10 and 11), a bent trailer hitch, or a crack in an irrigation pipe, there’s a proper way to do things. You may tell me “it’s not a big deal; just lay some metal in there,” but I won’t take the chance of being on the hook when the repair doesn’t hold and your crops don’t get water, or your trailer breaks off in traffic, or you fly off your bike.
If you bring me a cracked weld, I’m grinding it out first. If the original piece was garbage, I’m building you something stronger from scratch. If there’s a crack in a tube, I’m drilling out the ends, grinding out the crack, cleaning out the backside, backpurging if necessary, and then welding it. Yes, it takes longer. But it will last.
On the fabrication side, a distant cousin to “weld over the crack” is “I’ve got it tacked together; just put a pretty weld on it.” There’s a lot more to a good weld than the hand/eye coordination it takes to put down an aesthetically pleasing bead. How the material is prepped and tacked together plays a big part in the final product. It’s usually quicker for me to start from scratch than to undo and then redo the work you did, thinking you were helping out.
So those are the most common misconceptions I deal with. To be fair, when I explain why it will cost a little more than anticipated, most people get it. But maybe seeing this in writing will help your potential clients see that it’s not just a money grab, and also open your friends’ eyes to the effort it takes to perform a “quick fix.”