Wrenches

Most wrench trouble is a rounded nut, and most rounded nuts come from the wrong wrench: one that’s almost the right size, or one gripping only two corners. Pick the wrench that fits the fastener, and the job goes fine. WBC carries the three kinds that cover most work around a house, a truck and a shop.

Combination wrenches: the right size, every time

A combination wrench has an open end on one side and a closed box end on the other, both the same size. Use the box end to break a tight nut loose, because it grips all the way around. Switch to the open end to spin it off quickly, or where you can’t slip a box over the fastener.

WBC carries combination wrenches in 9/16 inch, 10 mm and 12 mm. Those three cover a lot of ground:

• 10 mm and 12 mm are everywhere on vehicles from the mid-1980s on, which are mostly metric.
• 9/16 inch is a common size on older American vehicles, trucks, farm equipment and a lot of household bolts.

Don’t swap close sizes between systems. A 9/16-inch wrench on a 14 mm bolt goes on, but it’s just loose enough to slip and round the corners. If the job is metric, use metric; if it’s SAE, use SAE.

Adjustable wrenches: one wrench, many sizes

An adjustable wrench has a movable jaw you set with a thumb wheel, so one wrench handles a range of sizes. WBC carries Channellock adjustables in 6 inch and 10 inch.

• The 6-inch fits in a pocket or a kitchen drawer. Faucet supply nuts, toilet bolts, small hardware.
• The 10-inch gives you more handle for more leverage and opens wider for bigger nuts. The one to keep in the truck.

The length on an adjustable tells you the handle; the jaw capacity, how wide it opens, is a separate number on the package. Make sure it opens wide enough for the biggest nut you’ll turn.

To keep an adjustable from slipping, snug the jaw tight against the flats before you pull, and check it again each time you reposition, since the jaw can loosen as you work. Pull so the force goes toward the fixed jaw, not the movable one. And when you have the exact-size combination wrench, use it; it’s always a better grip than an adjustable.

The pipe wrench: for threaded pipe

A 14-inch heavy-duty pipe wrench is the tool for threaded steel pipe and fittings: gas and water lines, well pipe, the galvanized fittings on a stock tank or a frost-free hydrant. Its serrated jaws bite into round pipe, and the harder you pull, the harder they grip. Fourteen inches is the usual starting size for household and ranch plumbing, with enough handle to break a fitting that’s been rusting in place for years.

Use two on a pipe joint, one to turn and one to hold the fitting, so the force doesn’t twist the rest of the line.

Those teeth leave marks. Keep a pipe wrench off chrome, polished brass and plastic pipe, which it can scar or crush. On a round finished surface, a strap wrench grips without marking; a smooth-jawed adjustable belongs on a fitting’s flats, and plastic fittings go together the way their instructions say.

The Pick

For metric vehicles and equipment, the 10 mm and 12 mm combination wrenches. For older trucks, farm equipment and inch-size bolts, the 9/16. A Channellock 6-inch for the house and a 10-inch for the truck. And the 14-inch pipe wrench for threaded pipe.

Frequently Asked Questions

Why does my wrench keep rounding off nuts?

Usually it’s a near-fit wrench, a metric wrench on an SAE nut or the reverse, or an adjustable that’s loose on the flats. Use the exact size, and use the box end to break a tight nut loose.

What’s the difference between a combination wrench and an adjustable wrench?

A combination wrench is one fixed size, with an open end and a box end. An adjustable opens to fit a range of sizes. The fixed wrench grips better; the adjustable saves carrying a whole set.

What size pipe wrench do I need?

A 14-inch pipe wrench is the common starting size for household plumbing. Check the wrench’s pipe capacity against the pipe you’re working on.

Can I use a pipe wrench on chrome or plastic?

No. The serrated teeth will mark chrome and can crush plastic pipe. A strap wrench grips round finished surfaces without marking; use an adjustable only on a fitting’s flats.