Heat tools can soften old paint, thaw frozen locks, solder electrical and plumbing connections, or even weld iron. The key to effectively using heat tools is to match the right heat output to the right task. A handheld propane torch is suitable for most household tasks.
This guide describes the different types of heat tools and their uses for home improvement tasks.
Heat Tool Safety
Safety First: As Tom Silva puts it: “You have to imagine what could happen, and protect yourself” against it. Two of every 10 homeowners who tackle a DIY project will wind up injured, according to TOH reporting — and heat tools demand extra vigilance. Use polycarbonate goggles rather than standard glasses, since a blink won’t stop a flying spark or shard, and wear a tight-fitting respirator with replaceable filter cartridges when working around chemical fumes from soldering flux or heated coatings.
Always wear appropriate protective gear when working with heat tools, including:
- Safety goggles
- Heat-resistant gloves
- Non-flammable clothing.
Work in a well-ventilated area and keep a fire extinguisher nearby. When using gas-powered torches, check for leaks before ignition and never leave a lit torch unattended.
Heat-Stripping Technique: When using a heat gun to strip paint, develop a rhythm between heating and scraping. Hover the device over the surface, and when the paint bubbles, slowly move the heater along so that you’re scraping and heating in unison. Always keep a metal paint tray handy for when you take a break and need to set the device down — never place a hot heat gun directly on a flammable surface.
Pro Tip: Tom Silva, This Old House general contractor, emphasizes that safety gear is about more than just having it on hand: “When it comes to protective equipment, I choose what fits and allows me to move easily.” A poorly fitting glove or fogged-up goggle can be just as dangerous as no protection at all, so check the performance rating and make sure your gear doesn’t compromise your dexterity when working with heat tools.
Types of Heat Tools
There are several types of heat tools available for home improvement projects: torches, heat guns, and soldering irons.
Understanding Heat Ranges: As TOH contributor John Kelsey explains, a little heat burns right through some thorny home fix-up problems. At the low end, 200 to 400 degrees Fahrenheit, heat softens old paint and putty. At the higher end, 400 to 800 degrees, it can thaw frozen locks and rusted nuts and solder electrical and plumbing connections. Still more firepower, up to 3,000 degrees, will braze metals and cut or weld iron and mild steel.
Torches
Torches use gas as fuel to produce flame.
- Propane torches are ideal for soldering copper pipes, brazing, and heating frozen pipes and rusted nuts.
- Oxygen-fuel torches use MAPP (methylacetylene-propadiene) or propane gas. They are suitable for cutting and welding iron and steel but don’t produce as sharp and efficient a flame as oxy-acetylene torches.
- Oxygen-acetylene torches are the most powerful option, capable of brazing, cutting, and welding steel. However, they require more skill and safety precautions to use effectively. Do not use this type of torch without training.
Heat Guns
Electric heat guns produce a concentrated stream of hot air. They’re excellent for softening old paint, putty, and asphalt tiles, as well as heat-shrinking plastic films and electrical tubing. Some models can be used for soldering with special attachments.
Soldering Irons
Soldering irons come in two main styles: pencil-style irons and soldering guns.
- Pencil-style irons take longer to heat up but are less expensive.
- Soldering guns offer quicker heating and more power. Both types are effective for soldering electrical connections and other small-scale applications.
Pro Tip: TOH plumbing and heating expert Richard Trethewey notes that MAP gas — a methyl acetylene propane mix — produces a flame about 15% hotter than standard propane, making it ideal for larger fittings where you need heat to penetrate all the way through. But on smaller fittings, he cautions, it can actually be too hot. When soldering, Richard advises applying the smallest bit of the tip — the hottest part of the flame is right at the tip — to one side of the fitting, then waiting until the flux bubbles completely from the other side before feeding solder.
Match Heat Output to Your Task
Select the right tool and heat level for your project and start with the lowest effective temperature. Increase temperature as needed to avoid damaging materials.
| Level | Temperatures (Fahrenheit) | What It’s Best For | Tool Needed | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hot | 200-400 degrees | Softening paint and putty | Heat gun | ||||||||||||||||||||||
| 350-840 degrees | Soldering: joining metals with a low-temperature metal filler | Soldering iron | |||||||||||||||||||||||
| Hotter | 840-1,500 degrees | Brazing, soldering with hard filler | Propane torch | ||||||||||||||||||||||
| 1,300-1,600 degrees | Cutting steel | Oxygen-acetylene torch | |||||||||||||||||||||||
| Hottest | 1,250-2,800 degrees | Welding: melting metals (typically aluminum, iron, or steel) together | Oxygen-acetylene torch | ||||||||||||||||||||||
| Level | Temperatures (Fahrenheit) | What It’s Best For | Tool Needed |
Additional Heat Tool Considerations
When working with heat tools, especially torches, ensure you are in a well-ventilated area. Fumes from certain materials can be toxic, and proper airflow helps dissipate potentially harmful gases.
Tool Maintenance
Regular maintenance of your heat tools ensures they function correctly and safely. Check for signs of wear, clean the tools after each use, and replace any damaged parts promptly.
Choosing the Right Fuel
Different torches require specific types of fuel. Ensure you are using the correct fuel for your torch to maintain efficiency and safety. For example, propane is commonly used for general household tasks, while oxy-acetylene is necessary for more intensive welding jobs.
Pro Tip: TOH general contractor Tom Silva stresses the importance of proper tool maintenance at the end of every work day. For corded heat tools like heat guns and soldering irons, he advises tying each cord into a figure eight and letting it hang loose rather than wrapping it tightly around the tool body: “If you pull the cord tight and wrap it around the body, the cord’s wires will eventually break, just like a shirt hanger that’s been bent too many times.”
When to Call an Expert
When considering whether to undertake a project involving heat tools on your own or to hire a professional, several factors come into play, including the complexity of the task, your skill level, and safety concerns.
Simple tasks that involve basic skills and minimal risk can often be handled by DIY enthusiasts. These include:
- Softening paint and putty: Using a heat gun to soften old paint or putty is relatively straightforward and can be done with proper safety precautions.
- Soldering electrical connections: Small-scale soldering jobs, such as joining electrical wires, can be managed with a soldering iron, especially if you have experience with basic electronics.
- Thawing frozen pipes: A propane torch can be safely used to thaw frozen pipes if you take proper precautions to avoid fire hazards and ensure good ventilation.
Doing the work yourself can save on labor costs. You can work on your own schedule without having to coordinate with a professional.
But more complex and high-risk tasks should be handled by professionals to ensure safety and proper execution. These include:
- Welding and brazing: Using an oxygen-acetylene torch for welding or brazing requires advanced skills and knowledge of safety procedures. Improper use can lead to serious injuries or property damage.
- Cutting steel: Precision and safety are critical when using high-heat tools to cut steel. Professionals have the necessary equipment and expertise to perform these tasks safely.
- Large-scale electrical work: Soldering electrical connections in large or critical systems should be left to licensed electricians to ensure compliance with building codes and safety standards.
Professionals are trained to handle potentially dangerous tasks, reducing the risk of accidents. Professional work also often comes with warranties or guarantees, providing peace of mind.
Hiring a professional can be more expensive, but it ensures the job is done safely and correctly. Ensure you hire someone with the proper certifications and experience for the task at hand.
A Case for Caution with Heat Tools on Old Homes: During the Arlington House project, the TOH crew weighed the risks of using heat for paint removal on the home’s exterior. As one expert on the project explained: “I really don’t like the idea of coming up to a house like this with a blowtorch cause it’s old wood. It’s dry. And why take the risk of having some of it catch on fire.” Instead, they reserved heat-based stripping for smaller, removable pieces like trim details or posts that could be brought to a safer work area — a smart approach any homeowner should consider before firing up a torch near old, tinder-dry framing.
Our Conclusion
Understanding when and how to use torches, heat guns, and soldering irons can significantly enhance the efficiency and safety of your home improvement projects. Always prioritize safety by wearing protective gear and working in a well-ventilated area. Match the right heat tool and output to your specific task, and maintain your tools regularly to ensure they remain in good working condition. By following these guidelines, you can effectively use heat tools for various applications around your home.
