My earliest memory of truly learning about conduction was when I was an 11-year-old Boy Scout at my first jamboree. We had a fire going at our campsite and my scoutmaster had fashioned a steel pipe between two forked steel uprights pounded into the ground to hold a big pot of pork and beans over the blaze.

“Danny, take the pot off the fire and bring it over here,” my scoutmaster said. And then he added, “Be careful.”

So, being young at the time, and a transplanted city kid, I walked over and looked at the pipe and the pot of bubbling beans. I reasoned that the only way to get the beans off the steel pipe would be to use a stick to slide the pot away from the flames and over to the end of the horizontal pipe. Then, all I would have to do would be to lift the pipe off the forked upright with my right hand and slide the pot off with my left hand. I would then carry it triumphantly to my scoutmaster and fellow scouts. I wondered if I might get a merit badge for this.

Conduction followed.

When I was done doing the dance of pain and flapping my blistered palms in the air, my Scoutmaster shook his head and gave me a stick of butter to hold, which didn’t help much. We had no ice and a hospital was out of the question. It was 1961 and we were Boy Scouts.

Oh, and he told me to use the potholder next time.

Which is why I cringed when I watched Gary Wilson of Northampton, Mass., solder a ball valve onto a copper pipe and wipe the joint with his bare fingers. I wasn’t there in the boiler room with him. Gary had posted a video of this on The Wall at HeatingHelp.com. He titled the thread, How to Solder 101.

It involves a torch, as all solder jobs do, but Gary wasn’t holding a roll of solder. He had just a stub, not more than an inch long. He fed the solder into the space between the valve and the tubing with his bare hand, not really moving the flame out of the way as he did so. I couldn’t see his face but I’m certain it was a mask of concentration. The fitting drank the solder and Gary wound up with a bit about the size of a tiny pearl. He poked that into the space with his bare thumb. It was like watching a close-up magician play with flowing lava.

But about the wiping: Gary used the torch for a few more seconds and then gave the joint three quick swipes: bare index finger, bare thumb, and bare index finger again. Swipe, swipe, swipe. He did it like he was moving an ace to the top of a deck. My jaw dropped.

I watched the video a dozen times and cringed each time I did.

Gary posted these words below the video: “Don’t do this at home.”

One of the Wallies who hangs out on the site asked Gary if he did this to keep his fingerprints out of the National database. Gary answered that he thinks he still has fingerprints but his eyesight isn’t what it used to be so he really can’t be sure.

I cringed again.

Another guy asked why he used such a short piece of solder and he said that it was the end of the roll and that the old-timers told him that the diameter of the copper tube determines the length of the solder, and he found that to be true since the 80s when he first entered the business. That shorty was just enough for that joint.

Then someone asked if he could do the bottom of the ball valve or a horizontal fitting the same way. Gary said that horizontal is actually less of a challenge.

“I just drop the nubber of solder right on top,” he said. “Sorry, I can’t do this trick on the upside-down.”

I wondered how he learned that he couldn’t do that.

And speaking of pain, another of the Wallies wrote: “The most pain I ever had was from soft solder that landed on top of my fingernail. I never realized how much that could hurt.”

Cringe, right?

That’s the “ouch factor” in action.

Gary Wilson responded by saying: “After thousands of solder joints, getting burned is not a big deal to me. I get dripped on once in a while when I’m near one of the other dudes who is soldering. I’m not that dull; I can feel it and it doesn’t feel good, but I’ve become used to it.

“A month or two ago, a blob landed on my arm. I called attention to it as it burned into my skin, showing my employee how he had just roasted me. It just stings for a little bit. Ha ha.”

How’d you like to be that employee right about then?

Gary continued: “It’s kind of like the old-timer electrician that subs for our regular electrician. To see if a wire is hot, he puts one fingertip on a metal box or the neutral wire, and then he taps the black wire with the tip of his other finger. Now, to me, that’s nuts.” 

Yeah — to me, too.

When I was young, I spent a day with an old-school oil-heat guy who used to tell the temperature of the hot water flowing through a supply pipe with his bare hand. That hand had more calluses than a podiatry hospital. He’d wrap it around the pipe, hold it long enough to make me cringe and then he’d call the temperature, “One-eighty,” he’d say, or “One-sixty-five,” if it was a return pipe on a cold day. I’d make my questioning face and he would take out a pocket thermometer. He said he carried that only to make me a more-faithful person. He’d check the temperature with the thermometer and it was always what he said it would be.

That man was the alpha dog at his shop and all the young people learned his ways. I never tried his trick because of, well, the jamboree thing.

But back to Gary Wilson.

Another of the guys posted: “I would have loved to have you work for me. Normally, there is about half-pound of solder on the floor after just a water heater install.”

To which Gary replied: “That’s funny. I once had a guy build a pyramid with solder around a two-inch fitting. I was so bugged out I saved the pyramid — I may still have that fitting someplace. I cut it out and it was hilarious. I put it back together myself and told him that if the fitting isn’t drinking the solder then he needs to stop because he has a problem, and more solder isn’t going to solve that problem.”

How’s that for great advice?

And in case you’re wondering, no, Gary doesn’t wet his fingers before wiping those joints barehanded, and he doesn’t use any sort of gel on his hands either. You know how I know this is true?

Because he said so.

And some guys just don’t say ouch, no matter what.

This article was originally titled “The ouch factor” in the February 2018 print edition of Plumbing & Mechanical.