What are Flare Nut Wrenches for?

[bonneyman]

I have a Bonney combo wrench with a flare nut end and a normal box end, both 7/8. It doesn't have any offset, which is nice in certain situations.

Those line wrenches have the thickest box ends of any Bonney's, and thick shanks. You got a tight fastener - the box end of a Bonney line wrench will do it! My set of those only goes up to 3/4". Missing the 4 bigger sizes.

 

[Jacobson]

I just want to get me a basic set and get this off my list.
I basically buy HF and Sears stuff for once a year use.

$30
http://www.sears.com/craftsman-5-pc-flare-nut-wrench-set-metric/p-00942013000P

$20
http://www.amazon.com/dp/B000NPUJOE/?tag=atomicindus08-20

GWrench $45
http://www.amazon.com/dp/B000NI93SE/?tag=atomicindus08-20

GearWrench Flex head $40
http://www.amazon.com/dp/B002BHXRM8/?tag=atomicindus08-20

Williams $50
http://www.amazon.com/dp/B001DNTR4S/?tag=atomicindus08-20

 

[JBradley500]

If you're looking at spending 40-50 dollars on them I would do one of two things.

1.) The buy one get one free Gearwrench sets from the site of your choice.
http://www.nationaltoolwarehouse.co...mGGgUvUY_cZbqxbfL_v7py_0RKMIuARHrLhoCNynw_wcB

2.) Keep watching eBay and buy a set used. I got the 11 piece SK set for like $45. You can also find used Snap-On SAE or Metric sets for the same price they are asking for those Williams or Gearwrench you posted.

 

[Tronyadorable]

Here's one of those very, very rare moments when the wallet has to come out for a wren$h. Only because it has moving parts

 

[toplessHO]

Here's one of those very, very rare moments when the wallet has to come out for a wren$h. Only because it has moving parts

those wouldnt work in about 90% of the places I use flare nut wrenches on. too big... that said everyone needs a set of crows foot flare nut wrenches
just wish mine had the multi angle hole for the extension.

 

[raiderhillbilly]

This!
And if you can get enhanced broaching, the chances of crushing and rounding the nuts drops even further. I've found the full polish Bonney's to be really good on HVAC fasteners But they didn't make them in metric.

Those are beautiful wrenches! Bonney flare nut wrenches are the best.

 

[deter]

soooo.... these wrenches are thicker and provide support on more sides because the fittings that they are used on are typically a soft material...
you are welcome

 

[Jacobson]

If you're looking at spending 40-50 dollars on them I would do one of two things.

1.) The buy one get one free Gearwrench sets from the site of your choice.
http://www.nationaltoolwarehouse.co...mGGgUvUY_cZbqxbfL_v7py_0RKMIuARHrLhoCNynw_wcB

2.) Keep watching eBay and buy a set used. I got the 11 piece SK set for like $45. You can also find used Snap-On SAE or Metric sets for the same price they are asking for those Williams or Gearwrench you posted.

I'm not sure getting a free set of SAE will do me any good.
Just extra clutter. Rather just get metric only.

Yea, good idea, I will look on Ebay, since I'm not in any hurry.
I'm going to get 9mm to 21mm. Full set.

Snap-on looks overpriced, even in the used market.
I'm seeing $100+, so I will exclude that from my search results.
Seems like people are willing to pay 80% of new for a used SO set.

 

[Jacobson]

Looks like Sunex gets bad reviews
http://www.amazon.com/dp/B000XW4CCM/?tag=atomicindus08-20

 

[Jacobson]

I think a $30 Craftsman set might be good for me

I have 2 choices for $30:
Both sets have 9-17mm
One set has the 16x18mm
Other set has the 19x21mm

Which is more common for light auto use?

http://www.ebay.com/itm/Craftsman-U...1277840600&pt=Motors_Automotive_Tools&vxp=mtr


http://www.sears.com/craftsman-5-pc-flare-nut-wrench-set-metric/p-00942013000P

 

[Lassen Forge]

Flare wrenches are a compromise between a box wrench (which gives you contact on all edges of a fitting but won't fit because of the line that runs through it) and a open end, which will deform the fitting, and at best cause it to leak, at worst will not allow it to go back together, which is why you NEVER use an open-end or crescent wrench on these... Plus they're strong enough (the good ones at least) not to deform.

Why is this imiportant?

It keeps that fitting round. On compression fittings on copper (Water and some fuel lines) or stainless/carbon steel (brake lines, fuel lines, etc.) or hydraulic fittings you want to keep that "nut" as round as you can.

Also, those fittings can be stuck tight like a SOB (for some reason analog oil gauge fittings are the worst!) and that flare wrench can give you the best chance of getting it apart.

Most important - DO NOT SKIMP ON QUALITY! THis is NOT the tool you want to save $20 on by hitting up harbor fright... especially when you remove that hydraulic brake fiting on an early 50's Rootes Sunbeam - and you destroy a fitting you have to now have made in a machine shop, when you finally find a machinist who's willing to make a custom one-off brake system part.

It was the first pair of socket sets I bought from the Matco ruck guy (He was close to 70 then, hope he's still around, what a gem of a gentleman!) - the standard and metric flare nut wrench socket sets - because of the above mentioned brake system f***up I did as an early 20-something apprentice mechanic doing someone a favor. And I was damned lucky to find a guy 2 weeks later who would turn me a pair of those cursed flarenuts, as long as I forgot his name, and gave him $100 cash for the work. EXPENSIVE lesson to learn.

 

[n8n]

Thanks Steve. It sounds like flare is better for more contact area but when you can't use a closed box end. So, when should you ever bother using open end wrenches if you have both box end (best) and flare nut (2nd best) ?

Square nuts?

I almost never use open ends... box end or socket 99% of the time.

 

[Jacobson]

Square nuts?

I almost never use open ends... box end or socket 99% of the time.

But in those cases when a socket won't fit, then you use a box end?
The only times you use a flare nut then, is when there is a like attached.
There is never a reason to use a flare nut when a box end can work, right?

 

[bonneyman]

But in those cases when a socket won't fit, then you use a box end?
The only times you use a flare nut then, is when there is a like attached.
There is never a reason to use a flare nut when a box end can work, right?

Right. Flare wrenches are great on soft fittings (brass, aluminum, soft steel) where deformation would lead to leaks. Mainly on fasteners that are holding a line of some sort (fuel, water, brake, refrigerant, etc).
I sold a spare set of Bonney flares to a friend, and he comes back and tells me how he's been getting nuts off that regular box ends have squashed. And he didn't have any Loc-Rite box ends, so, he backed them off with a flare wrench. I "kindly" told him not to expect the wrenches to last if he did that all the time.

 

[Strouty]

The one thing we need to know from the OP is where they live. If they do not live in the rust belt any brand will most likely work, if they are in the rust belt, well……….

Then you better prepare to spend some money on a good set our prepare to start swearing at your wrenches. Also the snap on sets that you see for $100 on ebay are not 80% of the original price, they are about 40% of retail. The 9 to 21 set is $274 retail.

 

[marinusdees]

For a flare nut. If you don't know what a flare nut is, you don't need a flare nut wrench.

 

[wagzilla]

I think a $30 Craftsman set might be good for me

I have 2 choices for $30:
Both sets have 9-17mm
One set has the 16x18mm
Other set has the 19x21mm

Which is more common for light auto use?

http://www.ebay.com/itm/Craftsman-U...1277840600&pt=Motors_Automotive_Tools&vxp=mtr


http://www.sears.com/craftsman-5-pc-flare-nut-wrench-set-metric/p-00942013000P

I would buy a good one, if you mess up a fitting it will cost you time and money, The craftsmen have always flexed and I did not have much luck besides them giving me a new one.

James

 

[Jacobson]

So, Craftsman are considered bad flare nut wrenches? Everything I've ever used by Cman has worked great for my weekend use.

 

[n8n]

So, Craftsman are considered bad flare nut wrenches? Everything I've ever used by Cman has worked great for my weekend use.

I've spread c'man (raised panel) flares before on rusty but not really destroyed looking VW brake lines. After a while I started clamping vice grips over the wrench when breaking a fitting free for the first time. I finally got rid of 'em and got Snap-On SAE flare wrenches and S-K metric ones. Time will tell if they're better but word on the street is they should be.

To answer a question you asked farther up, the only real use for flare wrenches in an automotive context is for tubing nuts (hence the name) as used on brake lines, power steering lines, transmission cooler lines, etc. For anything that has access for a socket or box end I would use one of those as they are much stronger. Flare wrenches are a necessary compromise for those specific fasteners. In fact, if I know a line is not salvageable I usually cut it and use a socket so as to save the other side of the fitting and possibly be able to reuse the tube nut (as often you think your FLAPS should have it, but they don't... and you don't have one in your junk box)

 

[sonvolt]

Definitely not wrenches you want to skimp $$ on. Snap On is at the top of the heap. I've had excellent success with my SK and Bonney sets. You definitely get what you pay for in this arena

 

[Wakefield]

A little PB Blaster or Kroil on the tube nut fitting the day before tackling them with the flare wrench a good idea?

 

[n8n]

A little PB Blaster or Kroil on the tube nut fitting the day before tackling them with the flare wrench a good idea?

Darn near mandatory, unless you live in a desert or only work on new cars.

Sent from my XT897 using Tapatalk

 

[plott hound]

the flare nut will deform under load from a wrench and cause it to bind on the threads. the more you can spread the load the less likely it will deform.

bingo!

 

[Jacobson]

What are good used brands besides Snap-on?
I am interested in tier 2 brands to search for.
What brands are in #2, b/w Snap-on and Craftsman ?

1: Snap-on
2: Mac? SK? Williams? BluePoint? BlackHawk? Proto? Matco?
3: C-man, Gearwrench, etc.

 

[jeepinerdeep]

What are good used brands besides Snap-on?
I am interested in tier 2 brands to search for.
What brands are in #2, b/w Snap-on and Craftsman ?

1: Snap-on
2: Mac? SK? Williams? BluePoint? BlackHawk? Proto? Matco?
3: C-man, Gearwrench, etc.

Mac makes a decent set, but on the used market are not all that much cheaper than a set of Snappys.

 

[AndrewV]

GearWrench
Proto
Carlyle
Sk
Armstrong
Williams usa

All good choices.

 

[Jacobson]

Right. Flare wrenches are great on soft fittings (brass, aluminum, soft steel) where deformation would lead to leaks. Mainly on fasteners that are holding a line of some sort (fuel, water, brake, refrigerant, etc).
I sold a spare set of Bonney flares to a friend, and he comes back and tells me how he's been getting nuts off that regular box ends have squashed. And he didn't have any Loc-Rite box ends, so, he backed them off with a flare wrench. I "kindly" told him not to expect the wrenches to last if he did that all the time.

Can you explain to me how these flare nuts "deform"? Why are they softer than normal nuts and bolts that do not deform?

How do box end wrenches "squash" these nuts? Wrenches do not compress the nut like pliers, do they?

 

[pi_guy]

Most flare wrenches are 6 point.
I do not understand how somebody could use a box end wrench on a line fitting such as a fuel line. But plumbing fitting are soft alum, brass or mild steel. If you have a flared line such as used for brakes the fitting passes the line through it so it will not have the same strength as a bolt. Aluminum AN wrenches are thicker than a standard open end wrench which helps to not deform the fitting. But fitting in VW drum brake cylinders normally take a bit of force to unseat and trying with anything but a flare wrench will lead to damage and most likely a line replacement.

 

[Jacobson]

Why are flare nuts made of soft material? Why not just make them out of steel?

Why does damaging the soft nut lead to line replacement?
What exactly happens when it gets crushed?

 

[creativecars]

Why are flare nuts made of soft material? Why not just make them out of steel?

Why does damaging the soft nut lead to line replacement?
What exactly happens when it gets crushed?

Some are steel, but many are not. Even a hollow steel nut is much softer than a much more robust regular nut or bolt. Add rust and you really need a boxed wrench, which will not work because the line. So a very strong wrench with a smaller opening for the line is needed.

 

[abk241]

When do you need a flare nut wrench?
What situation or fastener where a regular wrench not work?

http://www.sears.com/craftsman-5-pc-flare-nut-wrench-set-metric/p-00942013000P

It's not 'when' so much as 'where' you use them.
They are designed with an opening to fit over tubing where you obviously cannot use a box end.
The flare nut wrench gives 5 contact points as opposed to 3 for the open end wrench.

 

[OLEJOE]

Might work a\on an O2 sensor also.

 

[Jacobson]

Ok, so they are softer b/c they are hollow?
But, why are they typically made of softer metal?

 

[creativecars]

Yes, because they are hallow and the tube that runs through it is also hallow.

Some racing type fittings are aluminum for weight. Aluminum and Brass are soft metals, two brass fittings can be tightened together without a sealer and not leak. If one is brass and the other is steel the brass will conform to the steel line or fitting. There are probably other reasons, but that is what I can think of right now.

 

[Sal Bandini]

I would buy a good one, if you mess up a fitting it will cost you time and money, The craftsmen have always flexed and I did not have much luck besides them giving me a new one.

James

I tried my Craftsman on a fitting and it didn't work. Used my neighbor's Snap-On and it loosened right away.

For this type of tool I'm willing to to spend more money.