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Flare wrenches versus open ended?

uart

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What's the main advantage of flare wrenches compared to open ended? Are they stronger or is it just that they're less prone to rounding a nut?

Currently I don't own any. I'm just thinking about whether they're worthwhile getting?
 
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jdl25

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Flare nut wrenches are both stronger and less prone to rounding than an open end. They are needed for alot of line fittings and when you need them you will know it. I wrench on my own stuff only and I am glad to have them in the box.
 

WR250F

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Flare nut wrenches are particularly useful when working on soft(er) metal fasteners like brass and aluminum

Depending upon what you're working on, you may find them essential, or merely nice to have.

For some of what I do, they are a must
 
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uart

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Thanks for the input guys. So the most specific case where you'd really want them would be soft metal fixtures in places like lines and hoses where you cant get a socket or box end there. But they could also be useful anytime you have to swing a bit of torque and open ended is the only other option that has access. Does that sound about right?
 

GRX

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Thanks for the input guys. So the most specific case where you'd really want them would be soft metal fixtures in places like lines and hoses where you cant get a socket or box end there. But they could also be useful anytime you have to swing a bit of torque and open ended is the only other option that has access. Does that sound about right?
That is pretty much it. If you compare the two types, it is easy to see how the flare wrench directs the force on all points instead of just two as a regular open end does.
 

Alchymist

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"Flare"wrenches - the name says it all - originally designed for the brass fittings used on flared copper pipe. The brass fittings were quite soft, and an OE would often round them off. Have since become the go to tool for all kinds of softer fittings, especially for tubing applications.
 

Gary S

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As stated, flare wrenches were designed for brass and other nuts commonly found on fuel lines. Because of the softer materials the nut is constructed of, the wrench needs more contact area to protect the nut from damage.

In my experience, open end wrenches are much stronger than flare wrenches. I've "sprung" flare wrenches, but never "sprung" an open end wrench. Less metal on a flare wrench means weaker wrench. And, flares have to be made with less mass or they will never fit in tight spots where you want the wrench 3/4 around the nut.
 

Larwyn

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It's no coincidence that those soft fittings on copper lines are called flare nuts. The flare on the tubing is the seal the flare nut holds it in place. Thus the wrench to tighten/loosen them is called a flare nut wrench.
 

Wakefield

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As stated, flare wrenches were designed for brass and other nuts commonly found on fuel lines. Because of the softer materials the nut is constructed of, the wrench needs more contact area to protect the nut from damage.

In my experience, open end wrenches are much stronger than flare wrenches. I've "sprung" flare wrenches, but never "sprung" an open end wrench. Less metal on a flare wrench means weaker wrench. And, flares have to be made with less mass or they will never fit in tight spots where you want the wrench 3/4 around the nut.
The flare nut wrenches that I have look to be more delicate than my open end ones of the same brands I think they are more compact for clearance. And expensive so they should mostly be used on soft stuff where a box end won't go.
 

chevy.stroker

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My experience is this:

Of all the tools in your toolbox that need to be of the highest quality flare wrenches is one of them. I have had the most experience, from a quality point of view, with SO and Mac brand flare wrenches. Before that I owned the Craftsman raised panel. The first time you round a brake line and have to replace it will be the time you will understand what I am saying.

When you are paid by the job they pay for themselves very quickly.
 

HandyManny

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What's the main advantage of flare wrenches compared to open ended? Are they stronger or is it just that they're less prone to rounding a nut?

Currently I don't own any. I'm just thinking about whether they're worthwhile getting?

As Gary S and Wakefield have said, as well as a few others:

Flare wrenches are designed to use on flare nuts, if you don't know what a flare connection is, then look it up, typically used in plumbing and fluid lines. They are designed to securely fit and grip around most of the surface of the often softer flare nut (brass, sometimes stainless) to avoid rounding it. I wouldn't say that flare wrenches are stronger or weaker than an average open end wrench. The main advantage being that they grip more surface area than an open end wrench and flare wrenches tend to be shorter for a reason. High leverage or torque generally isn't needed with flare nuts, but finess in tight spaces is often needed with these. I would not advise using flare wrenches on regular nuts and bolts, this is kind of akin to using a spark-plug socket on a lug nut or some such.

Quite frankly I've always been able to use an appropriate sized adjustable wrench on most flare nut connections without any issues.
 
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uart

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Thanks everyone. It looks like I don't really need any flare wrenches then. My local parts stores has a really basic set 10-12, 13-14, 15-17 on sale for $5. Though I'm sure everyone here understands that not needing a tool is no reason not to buy it. :D Now if only our wifes/gfs could understand that too ;)
 

chevy.stroker

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Quite frankly I've always been able to use an appropriate sized adjustable wrench on most flare nut connections without any issues.

Wow, I guess your and my experiences conflict. Have you ever wrenched for a living? I rounded way to many brake lines off on wheel cylinders before I bought a set of SO flare wrenches.
 

HandyManny

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Wow, I guess your and my experiences conflict. Have you ever wrenched for a living? I rounded way to many brake lines off on wheel cylinders before I bought a set of SO flare wrenches.


Yes I've wrenched for a living - aircraft A/P for a few years off and on very early on, small engine mechanic, as well as a few manufacturing jobs, and construction/plumbing trade jobs over the years too, but was a professional pilot (bush, corporate, air carrier) for the vast majority of my career, 30+ years....the trick is just knowing how and when to use the right tool.
 

WR250F

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I've rounded/trashed more than one aluminum fastener with a open end.

With flare wrenches I haven't rounded one in years
 

groa944

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On audi/vw brake systems, I've had terrible luck with anything other than flare nut wrenches. Even middle of the road ones will spread to some extent on an older car that hasn't had the brake system apart since manufacture. The fittings are brass or something similar, and end up rounding off very easily. Then you're faced with replacing the line, or cutting and installing a new fitting.

The lifesaver for me has been the vise grip LW series (4lw, 7lw, 10lw). They're vise grips with a special jaw that clamps around the flare fitting. Now, I go straight to those and skip the flare nut wrenches.

I believe I found out about them from searching around on this board.
 

rockchucker

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I've rounded/trashed more than one aluminum fastener with a open end.

With flare wrenches I haven't rounded one in years

Now ya dunnit!

I ONLY use Flare Nut Wrenches on Hydraulic Lines and such. The first time you have to fix what ever you screwed up by using only an Open End Wrench you will buy a set and use them religiously. I will even go as far as to spray ONLY THE THREADS with just a touch of Kroil while protecting the Flare Nut with a Rag. You don't want Lube on the Nut you are trying to remove. Especially between the Wrench and the Nut. Make sure the Inside of the Flare Nut Wrench is clean also. You can also take a small Hammer and tap the outside of your Wrench before trying to remove the Flare Nut. This will sometimes help break it loose. Kind of like a Impact Gun.
 
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Octarine

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If you are looking at a $5 set, skip them. To get the value out of them you need a good set. They do come up used from time to time.
 

pipsters

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I must be the rarity. My car spent 8 years in NH, before I got it. Owned it for a good 6 or 7 years and did the brakes. First time I had ever worked on brakes in my life. All 4 calipers were easily opened to bleed using just a regular wrench, although I used the box end.

Also on the same car, taking off brake lines under the hood, it seems the flare nuts really aren't on all that tight. A regular wrench worked just as well. That being said, I can definitely see how the flare nut wrench does a much better job protecting the nut from rounding. I just got a Craftsman RP set and, honestly, they are great. Fit is very tight, and the metal seems to be the same as my RP wrenches which means they won't open on me. For $35 plus another $6 for the Allen 16x18, I got 10 flare nut wrenches that work for my needs.
 

JASTECH

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I had rounded a few brass and aluminum nuts on lines years ago when I was using std plyers and end groove plyers then Vise Grips and crushed nuts and ferrels, many leaks until I started buying my tools of the Snap-On truck. I have a set of SO flare wrenches now that I bought off the truck out of his "foreclosed" box over 20 yrs ago and are thick and strong as the day they were born.

Thanks, JASTECH
 

Outlawmws

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If you have a stuck nut, sometimes tightening a bit till it cracks ("loose"), then loosening will do the trick.
 

Seanbev24

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My Flank Drive Plus open ends have greatly reduced my need for them, but I still go for the flare nut wrenches first if the fitting is rusty or corroded. They're an absolute must for a pro and are highly recommended for the DIY type.
 

jamesc

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Ontario Canada
most under hood lines will loosen with an open end. now the under body of cars is different, once a car is a couple years old and has seen some winters I wouldn't dare using anything but a good flare nut wrench on any brake lines or powersteering lines.
 

crewchief888

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flare nut wrenches have saved my *** more than once trying to get old, rusted PS hoses off.

i try to save PS steering hoses, dealing with body lifts, engine swaps ect, sometimes having afew extra hoses around, i can work out what will fit.
i'm usually not overly concerned with rounding off a brake line, they usually need replaced anyway, i cut them off and use a 6pt socket on them.
i'm normally dealing with badly rusted, lines on trucks that have spent a lot of time in the mud.

for a few bucks in new lines, adapters, and SS flex hoses, it's worth not fighting a (sometimes) loosing battle


:beer:
 

GoBlue

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Thanks everyone. It looks like I don't really need any flare wrenches then. My local parts stores has a really basic set 10-12, 13-14, 15-17 on sale for $5. Though I'm sure everyone here understands that not needing a tool is no reason not to buy it. :D Now if only our wifes/gfs could understand that too ;)

You definitly dont need a $5 dollar set of flare nut wrenches. Cheap flare nut wrenches spread so badly that they work no better than an open end. If you are going to use cheap flare nut wrenches save your time and cut the line and use a socket.
 

diesel research

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Relying on only past experience of not needing a tool is generally a poor method.

They definitely have a purpose, and the cheaper ones "work fine"....until they don't. Best to have a quality set that fits and doesn't spread EVEN WHEN THE FITTING IS TIGHT. Judging the tools performance on an easy fitting is of little value.

"i always use adjustables" What can I make of this statement? That adjustables always work? Certainly not. Instead it means "I have not encountered enough variety of situations....yet"

It's kind of like an old timer telling someone "10mm wrench is useless, I've never needed one" Or a imported car owner telling a small engine mechanic that 7/16 is useless or not needed. They both simply lack enough worldly experience regardless of age.
 

wreckercologist

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If you have a stuck nut, sometimes tightening a bit till it cracks ("loose"), then loosening will do the trick.

I've also done this quite a bit. Works well.



I'm surprised no one else has brought these up:

http://buy1.snapon.com/catalog/item...4&group_ID=571&store=snapon-store&dir=catalog

http://buy1.snapon.com/catalog/item...4&group_ID=572&store=snapon-store&dir=catalog

These are the cat's ***. Crack the fitting loose with the flare end and speed the nut off with the open end. Great for all kinds of other soft brass fittings too.
 

chevy.stroker

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I'm surprised no one else has brought these up:

http://buy1.snapon.com/catalog/item...4&group_ID=571&store=snapon-store&dir=catalog

http://buy1.snapon.com/catalog/item...4&group_ID=572&store=snapon-store&dir=catalog

These are the cat's ***. Crack the fitting loose with the flare end and speed the nut off with the open end. Great for all kinds of other soft brass fittings too.

In my opinion the best wrenches you can buy. I wish they made a 1/4" and 5/16".
 

WR250F

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I have an S-K set that has proven to be very durable and without doubt one of if not the best money I've ever spent on tools.

One of my grandsons has a set he bought at O'Riely Auto Parts that is not the greatest.

HF sells a set under the Pittsburgh name, but I can't speak to their quality. I know NT sells a set too, but I've never worked with them.

I'm inclined to suggest in this instance, buying as much quality as you can.

Flare wrenches will never be as strong as an open end, or a box, but some are definitely better than others
 

Rico.

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I've always thought that everyone, be they amateur or professional
should buy the best quality flare nut spanners that exist. Socket sets
and ratchets amateurs can easily get away with just good quality stuff,
but the first time you mess up a nut and all the hassle that goes along
with it you will really regret buying cheap flare nut spanners.

I can personally recommend These Facom flare nut spanners I bought.
They are not cheap (They are about $180 for this set) but they are a
bit cheaper than Snap-On and they feel like they are made out of Diamond. :thumbup:


facom flare nut by Rico UK
 

porcupine73

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Buffalo, NY USA
I have Craftsman line wrenches in both RP and professional. They are Ok, but they don't always have a nice grip on the nut. I've been putting vise grips over the flare end to help it grip the nut more tightly. If/when I ever replace these, something higher quality will definitely be in order! I use them mostly on brake line fittings, but sometimes also I use them on the jam nuts on tie rod ends.
 

afazz

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Yes I've wrenched for a living - aircraft A/P for a few years off and on very early on, small engine mechanic, as well as a few manufacturing jobs, and construction/plumbing trade jobs over the years too, but was a professional pilot (bush, corporate, air carrier) for the vast majority of my career, 30+ years....the trick is just knowing how and when to use the right tool.

That sounds like an impressive career and please don't take this the wrong way, but rust isn't a factor in any of those jobs - especially "Out West" as listed in your profile. As you said knowing when to use the right tool is important, and I agree that an adjustable wrench is all you needed. But if you live in Buffalo, NY and need to remove a brake line on a 1995 F150, a top quality flare nut wrench is really your only hope.

I agree with everyone who said that high quality is the only option here, a low quality flare nut wrench is no better than a good open end wrench. I prefer Snap-on.
 

HandyManny

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That sounds like an impressive career and please don't take this the wrong way, but rust isn't a factor in any of those jobs - especially "Out West" as listed in your profile. As you said knowing when to use the right tool is important, and I agree that an adjustable wrench is all you needed. But if you live in Buffalo, NY and need to remove a brake line on a 1995 F150, a top quality flare nut wrench is really your only hope.

I agree with everyone who said that high quality is the only option here, a low quality flare nut wrench is no better than a good open end wrench. I prefer Snap-on.


I lived in the pacific northwest on the coast for a good many years. It's quite damp there about 9 months out of the year. :)
 
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