azchrisf
Well-known member
I know what they are for, but tell me, what is the purpose of them when you can just use a regular open end wrench?
Much obliged gentlemen!
Much obliged gentlemen!
Purpose of Flare Wrenches?
- Thread starter azchrisf
- Start date
BIG BACCHUS
Well-known member
If a flare nut is rusted the amount of torque you'll have to put on it may round off the fastener with a traditional open end wrench. Also, some of the fittings are made of brass, aluminum, etc. and are easier to round off. The flare nut wrenches allow you to apply more torque throughout a larger surface area on the fastener and thus increasing the likeliness of getting it off with out rounding the fastener.
anndel
Well-known member
You can use an open end wrench on flare nuts/lines but you stand a good chance of slipping and rounding the flare nut. Flare nut wrench (a.k.a. line wrenches) grip all corners of the nut, reducing the chance or slipping.
ddawg16
Well-known member
Once you have turned a six sided flare nut into a perfectly round flare nut, you will understand.
Hint...the flare nut is a softer material than a typical steel nut....at least it sure feels like it
Strouty
Well-known member
I use open end flare combos, but they have a much wider and stiffer open end so it won't hurt the fittings.
Ideally you would use a six point socket on every connection, but that pesky tube gets in the way every time!
Ideally you would use a six point socket on every connection, but that pesky tube gets in the way every time!
buffalobill
Well-known member
In the rust belt, often times line wrenches seem like a joke, no edges left to grip. I have them, but frequently resort to vice grips with sharp jaws, as the hardware is fubar.
Same here in Ontario. Mini Cobras work awesome on fittings if they fit !
Wamsutta
Well-known member
The flare wrench distributes the force evenly across all six sides rather than just two sides.
LNKMK8
Well-known member
Brake lines, transmission fluid lines, etc. The material is very soft, and typical open end wrench will destroy them. Once you have used them for their intended purpose, it becomes very clear as to why you need them.
Fedwrench
ALLIANCE MEMBER
you don't need rust to appreciate a good line/flare wrench. Many power steering hose fittings will easily round off if trying to use an open end wrench on them. As others have pointed out, better lines wrenches like the combination versions, will have slightly taller/thicker flare ends to grip the flare nut better.
mmason7764
Well-known member
With a flare nut wrench seems like it's a little easier to put all your force into rotating the wrench & nut. With an open end there is a tendency to bend the tubing if you're not careful. Especially if the tubing is not steel.
Finding a chewed up flare nut must be frustrating.
Mark
Finding a chewed up flare nut must be frustrating.
Mark
d.mcfarland
Well-known member
12 point flare nut wrench would be an absolute joke around here on anything not brand new.
Really? I've used my Bonney's many times on older, over-torqued fittings. Though it's less these days with all the metric fasteners, as the Loc-Rite flares weren't made in metric.
bob15
Well-known member
You would be amazed as to how well they actually work.
Have you honestly tried a set? Besides Bonney, Proto and Snap On both make them....so no excuse to not try them.
L5wolvesf
Well-known member
Actually there is, not all of AZ is the arid desert seen in movies and TV. There is also an area known as the Red Rocks of Sedona. The red color comes from iron oxide.
We use flare nut wrenches here too as thoroughly described here
Ign
Well-known member
He says he knows what they're for but then he asks what they're for.
This has gotta be a troll post.
This has gotta be a troll post.
mbshop
Well-known member
I had an so set. Rarely used. But when needed ? Priceless !
slip knot
Well-known member
Those 12pt bonneys are sweet. if you do much hydraulic work you will appreciate a set of 12 pts.
Many here already espounded the virtue of flare wrench. Not all flare wrench are created equal. I have both the SK and SO set. I have an extremely tight fitting to remove. The SK keep slipping and rounding off the corners so I switch over to the SO. Even with some rounding of the corners, the SO would not slip at all eventhough I put alot of torque on it so much so that the supporting bracket twisted. I was so impressed with the SO that I bought another set. So if you are going to get a set, get a high quality set. SO is really expensive. Wright make a high quality set for lower price. I have never use the Wright set so I don't know its performance.
paulsomlo
Well-known member
Thus far, I've gotten away without flare wrenches. I've used either a knipex pliers wrench or an adjustable wrench in good shape with nice clean jaws. With the adjustable, it's a matter of wiggle, tighten, wiggle, tighten, until there's no play. Granted, I don't wrench every day.
Yep. Was the only way I got the brake lines off of a Camaro that has been up on blocks in a New England backyard for 30 years.
It has all stainless brake lines now.
Finky198
Well-known member
You would be amazed as to how well they actually work.
Have you honestly tried a set? Besides Bonney, Proto and Snap On both make them....so no excuse to not try them.
I'm with you ^^^
I have Snap On 6pt sets and 6pt crows feet flare nut, I also use my father old set of 12pt snap on line wrenches they have come in very handy. He had them from working as an aircraft mechanic. All SAE in common sizes. I also have a set of 12pt tubing wrench in the larger sizes. And Snap On 1/4 12pt crows feet. I have yet to have one slip 12pt or other wise...
That bunch added to some knipex pliers cobras and pliers wrenches (as said above ) and your good to go the only other style would be for harder fitting and hoses a set of 4 way angle wrenches...
And you can pretty much tackle anything...
This is pretty much it.
Its easy to say flares are used for tubing, but still not understand why you need a speacial wrench. The answer is that tubing/flare fittings are not typically hardened steel. At low HRC levels, the normal and higher-HRC open end wrench, will simply dent and distort the nut vs turn it. Rust makes this worse, but is not always the issue. Thermal expansion/heat cycling and other types of corrosion come into play.
The flare wrench is designed to spread the turning force over the widest possible area, and generally increases surface area by 50-100%,which has the effect of making the dent-resistance of low HRC hardware act much more like a harder metal and turn the faster not simply deform in a plastic manner.
Lower quality flare wrenches tend to spread and open, which compromises the geometry and again puts the force on the small areas like the corners. The better ones like SO have stiff construction and relieved/flank drive profiles.
BTW, aslo as aluded earlier you can have several useful styles, either adding 2+ extra faces to get more area or by making a much thicker open-end with the usual shape (to get more area). IN general, the former are for breaking free and the latter for removal without risk of damage (open end is faster to engage/re-engage) as you work.
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Apart from the use on lines i use them often for brake caliper bleeders, stops them rounding when their caked in rust.
Normally after wire brushing the rust off they can be a good 1mm smaller than their original size, especially if its an older car.
Normally after wire brushing the rust off they can be a good 1mm smaller than their original size, especially if its an older car.
it's not always rust that makes it difficult, it's the fact that many fittings screw into dissimilar metals and get stuck, especially if they haven't been loosened in decades. fuel lines into carburetors and fuel pumps for example, aluminum or pot metal oxidizes, the alcohol in fuel doesn't help either. couple that with the fact that the nut is hollow and very thin, so it tends to collapse much easier than a nut.
thegrayham
Member
- Joined
- Oct 17, 2016
- Messages
- 7
Is Snap On the only source for flank drive style flare nut wrenches? I realize this isn't a necessary, but when dealing with the really stubborn and soft flare nuts, I like the piece of mind.
Cummins_Tech
Well-known member
- Joined
- Jul 5, 2017
- Messages
- 152
bob15
Well-known member
No. Bonney & Proto have the same style lobe design.
FYI: The Bonney is the originator of the "flank drive"......beating Snap On by a couple years
gordyy
Well-known member
As an Hvac tech back in the old days everything was flared . Right up until around the 60s when silver brazing took over and compressors became hermetically sealed ( and kept in a mayonnaise jar on funk and wagoners front porch) they were needed. R-22 or R 502 on a hot day just sitting without a running compressor had 250 to 400 lbs of pressure on the lines try getting a flare fitting tight enough to hold that with an open end or a channel lock or even Knipex pliers. Had a guy take over my job while I had my first knee replacement that loved the Knipex pliers. I did a lot of free warranty work behind those pliers and a brass or aluminum flare nut looked pretty nasty after the knipex hit it **** down the systems take apart cut tube install new flare nut re-flare fitting tighten with flare nut wrench recharge etc.
I believe every tool made has a use and is needed in its place.
I believe every tool made has a use and is needed in its place.
Mikeske
Well-known member
Matter of fact yes the Bonney flare nut wrenches were made in metric but not Loc-Rite
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sberry
Banned
I have proto and Cman. The cmans are junk. The proto are ok and maybe others are better. But on rusty old stuff I usually skip right over them and go to the straight jaw Vise Crips, 6 inch and 10. Could care less if it leaves a mark on some old ****.
They have their place and when you need them you do but on old a Vgrip can squeeze a brake fitting out of round and loosen the nut from the line. I squeeze it the other way 90 degrees to fix them on occasion.
They have their place and when you need them you do but on old a Vgrip can squeeze a brake fitting out of round and loosen the nut from the line. I squeeze it the other way 90 degrees to fix them on occasion.