Flare-Nut vs Regular Wrench: Which is Best for Your Needs?

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traditional wrench in use

We’re all pretty familiar with a normal wrench. They consist of two straight jaws with a rounded middle. The distance between the two jaws determines the size of the wrench.

You slip it around a nut you want to loosen, say a quick prayer and give it a twist. With a little luck and a blessing of the gods, it turns. If you have displeased the gods or if the nut is frozen in place by corrosion, the wrench slips and maybe even strips the nut. If you’ve have enraged the gods, your knuckle is bleeding because you knocked it against hard metal.

The box-end wrench was an innovation intended to correct much of that. Rather than a two-sided jaw, it fits along five of the six sides of a hexagonal wrench. As long as you can hold it firm against the turning surface, you probably won’t strip the nut and probably won’t bark your knuckle against something that causes pain.

Five-sided solution to problem hoses

But that’s not always very practical, especially when working on vehicles, where you need to loosen nuts to replace hoses. It also has special application in some plumbing jobs, where a lot of nuts are made of soft metal, which increases the odds of stripping the nut. And injuring your knuckle.

The solution is the flared wrench. A flared wrench is a hybrid of the traditional wrench and the box-end wrench. But instead of being completely enclosed, one side is left open so that there is room to fit the wrench around the hose before coming down around the nut.

The big advantage is that you now have a wrench gripping five sides of the nut, instead of the usual two, for a job where the much-more desirable six-side grip is impossible. Stripping is much less likely, especially if you’re dealing with soft metals.

Open side a slight weakness

The main drawback to a flared wrench is that because it is form fitted compared to a basic two-sided compatibility, it’s doesn’t quite possess the overall tool strength of a basic wrench. If a nut is really stuck in place, this elevates the chances that the wrench could break if you twist too hard.

On the issue of price, there’s not a big difference between a flare wrench and a regular wrench. But, really, this isn’t a matter of comparison shopping. Traditional wrenches have their own distinctive jobs to do and flared wrenches have theirs. Both are useful components if any home tool inventory.

A few final thoughts

Flare nut tools are the sort of tool that most home hobbyists won’t use every day, but when you need one it’s absolutely the right tool for the job. If you work on a lot of vehicles or machines that require you to loosen nuts to replace hoses, they’re a great option to avoid the heartbreak of stripped nuts and barked knuckles. They’ve also got great utility in your toolbox for plumbing jobs, or anything where you need to slide the head of your wrench around a protrusion to loosen a nut. The great thing is that they don’t cost appreciably more than a regular old set of traditional wrenches.

They’re no substitute for those old-style wrenches, however. Because they are form-fitted rather than drawing strength from crude design, they won’t withstand the pounding of a regular wrench, and at any rate it’s never a good idea to put a tool designed for specialized purpose through the rigors of everyday use unless you really need to.

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About the Author Adam Harris

Hi there! My name is Adam and I write for HealthyHandyman. I have a great passion for writing about everything related to tools, home improvement, and DIY. In my spare time, I'm either fishing, playing the guitar, or spending quality time with my beloved wife. You'll also often find me in my workshop working on some new project!