Can you solder copper pipe joints using unconventional torches? We put three different flame sources to the test: a tiny butane “crack pipe” lighter, a mid-range butane torch, and an oversized propane blowtorch meant for heavy-duty tasks. While professional plumbers typically rely on an acetylene B-tank or a propane torch designed for soldering, sometimes you have to improvise. Here’s what we learned about using unexpected torches to sweat copper.
Why Traditional Soldering Torches Are the Norm
Professional-grade torches (like those attached to a B-tank of acetylene or a dedicated MAP/propane kit) provide: • Enough heat to quickly bring the copper and fitting up to temperature
• A precise flame for controlled, uniform heating
• Reliable ignition and consistent fuel flow
When you deviate from these, you risk incomplete “cold” solder joints or burning the metal if the flame runs too hot or wide.
1) Tiny Butane “Crack Pipe” Lighter
This pocket-sized lighter had just enough flame to melt solder, but it took a long time to heat a simple coupling. If you’re stranded without your usual setup, it can work in a pinch for very small-diameter pipes—but expect an extended wait. Because the flame is extremely narrow, you have to move it around constantly to warm the entire joint evenly. It’s better suited for electronics or crafts than plumbing.
2) Mid-Range Butane Torch
A step up from a cigarette lighter, the mid-range butane torch provides more consistent heat and a bigger flame. This tool can heat a coupling fairly quickly—though not as fast as a dedicated plumber’s torch. Caution is still required to avoid scorching or uneven heat distribution, especially on larger fittings or thicker copper. It’s a decent backup for quick repairs if you don’t have your usual setup on hand.
3) Oversized Propane Blowtorch
At the other extreme, we tried a high-output blowtorch. This beast brings intense heat in seconds, making it easy to overheat or burn the flux if you’re not careful. While it will absolutely melt solder, controlling the flame and ensuring an even draw can be challenging. For large pipe sizes or if you’re used to moving fast on a job site, it might be overkill for delicate joints but can be tamed with experience.
Tips for Soldering Success Regardless of Torch
• Clean the Surfaces Thoroughly: Sand both the inside of the fitting and the outside of the pipe. Even exotic torches won’t fix a dirty pipe.
• Use the Right Flux: Apply a thin layer of plumbing flux and wipe off excess.
• Heat Evenly: Move the flame around the entire circumference of the joint. Don’t just hold it in one spot.
• Test Your Joint: Once cooled, a good solder joint shows a shiny ring of solder, with flux residue wiped off. If it looks dull or bubbled, you may have heated incorrectly or too briefly.
Conclusion
Yes, you can theoretically solder with an assortment of unconventional torches. But each tool presents its own challenges, such as lack of heat, too much heat, or uneven flame control. For routine plumbing tasks, stick to a tried-and-true plumber’s torch that produces enough heat quickly and uniformly. If all else fails and you’re forced to improvise, be prepared for slower heating with small flames or overly aggressive heat with large ones—and always double-check your final solder joint for reliability.
