More in Hand Tools

How to Use Torches, Heat Guns, and Soldering Irons-and When

You only need a little heat to burn right through some repairs.

Photo by Peter Meretsky
1 ×

 

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 (a stronger form of soldering that uses harder filler materials) and cut or weld iron and mild steel.

High heat for home use is created with electricity or by igniting a gas such as propane, MAPP (methylacetylene-propadiene), or acetylene, each of which burns hotter than the last. While these gases will burn on their own using the oxygen in the air, to generate the most heat they need to be burned together with pure oxygen from a separate tank.

The important thing is to match a tool�s heat output to the task at hand. A $245 oxy-acetylene torch can weld steel; it can also sweat copper pipes or caramelize cr�me br�l�e, but that would be overkill. For about $50 each, a handheld propane torch and an oxygen-fuel combo if you do a lot of fence or pipe repair should give you the heat you need in a manageable package.
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 (a stronger form of soldering that uses harder filler materials) and cut or weld iron and mild steel.

High heat for home use is created with electricity or by igniting a gas such as propane, MAPP (methylacetylene-propadiene), or acetylene, each of which burns hotter than the last. While these gases will burn on their own using the oxygen in the air, to generate the most heat they need to be burned together with pure oxygen from a separate tank.

The important thing is to match a tool�s heat output to the task at hand. A $245 oxy-acetylene torch can weld steel; it can also sweat copper pipes or caramelize cr�me br�l�e, but that would be overkill. For about $50 each, a handheld propane torch and an oxygen-fuel combo if you do a lot of fence or pipe repair should give you the heat you need in a manageable package.
2 ×

Torches

 

Torches

Torch
Photo by Peter Meretsky
Oxygen-fuel torch (MAPP or propane)
Good For: Cutting and welding iron and steel, as in fence repairs. These gases don't make as sharp and efficient a flame as an oxy-acetylene torch.
Pictured: Oxygen with MAPP gas, which always comes in a yellow cylinder. Propane is cheaper, but the MAPP flame gets slightly hotter.

Oxygen-acetylene
Good For: Brazing, cutting, and welding iron and steel. Caution: Acetylene is harder to control and more dangerous than other fuels. Visit a welding supply store for the goggles and other protective gear — and welding classes — you'll need to use it safely.
Pictured: A compact oxy-acetylene combo kit, typical of the way these torches are sold.

Propane torch
Good For: Soldering coper pipes, brazing, and heating frozen pipes and rusted nuts.
Pictured: A torch with an electronic ignition, which is safer and more reliable than a spark, and a flame-spreading tip that lowers the heat for softening paint and caramelizing foods.
3 ×

Heat Guns and Soldering Irons

 

Heat Guns and Soldering Irons

Illustration by Jennifer Thermes
Electric heat gun
Good For: Softening old paint, putty, and asphalt tile; heat-shrinking plastic films and electrical tubing; soldering (requires special attachment).
Pictured: A pistol-style gun with variable controls, which is safer than a single-temperature wand-style one.

Electric soldering tools
Good For: Soldering electrical connections.
Pictured: A pencil-styled iron (above right) and a soldering gun. The iron takes longer to heat up but is less expensive.
4 ×

The Hot Spots

 

The Hot Spots

A compact oxy-acetylene combo kit
Photo by Peter Meretsky
A torch flame has many parts, all with different temperatures. While different gases produce different flames, the hottest point of any flame is at the tip of the inner cone, where the pale flame meets the deeper-colored outer flame.

HOW HOT IS HOT?
HOT 200-400 degrees Fahrenheit Softening paint and putty
350-840 degrees Fahrenheit Soldering: joining metals with a low-temperature metal filler
HOTTER 840-1,500 degrees Fahrenheit Brazing: soldering with hard filler
1,300-1,600 degrees Fahrenheit Cutting steel
HOTTEST 1,250-2,800 degrees Fahrenheit Welding: melting metals (typically aluminum, iron, or steel) together


5 ×

Where to Find It

 

Where to Find It

Oxygen with MAPP gas torch
Photo by Peter Meretsky
Electric heat gun:
Heavy-duty variable temperature heat gun Model #8977-20
Milwaukee Electric Tool Corporation
Brookfield, WI
800-729-3878
Milwaukee Electric Tool

Electric soldering tools:
Weller universal multipurpose soldering gun with dual heat (140/100 watts) and Weller 25-watt lighted soldering iron
Cooper Tools, Barrie
Ontario, Canada
Cooper Tools

Trigger-start cast-aluminum torch head:
Model #TS4000T
Bernz-Omatic
Newell Company
Medina, NY
800-654-9011
Bernz-Omatic

Oxygen/ MAPP gas brazing/ welding/ cutting torch kit:
Model #OX2550KC
BernzOmatic

Torch gases:
Propane, MAPP, and oxygen all from BernzOmatic.

Oxygen-acetylene torch:
Model #WT5000
Campbell Hausfeld
Harrison, OH
800-543-6400
Campbell Hausfeld
 
 

TV Listings

Find TV Listing for This Old House and Ask This Old House in your area.