Flare nuts are often found on fittings and other components with tubing or other lines attached, meaning you cannot access them with a standard box end wrench. I suppose that you could sometimes work on them with the open end of a standard combination wrench, but most often flare nut wrenches are used when you know you’ll need them,
Flare nut wrenches are open end wrenches, but with narrower openings than the standard open ends on a combination wrench, and often have 6pt (non-ratcheting) or 12pt (often ratcheting) profiles with hooked openings instead of the parallel jaws of an open end wrench.
You place a flare nut wrench on top of a fastener, as opposed to sliding onto it from the side, as with a regular open end wrench.
Flare nut wrenches give you better access angles, and some slippage protection, so that the wrench stays more secure around a fastener.
These new Astro Pneumatic Ratchet and Release flare nut wrenches, 7120 for the SAE set, 7120M for metric, are a new hybrid tool that they say gives you the strength of a box end wrench, with the accessibility of a flare nut wrench.
The new wrenches close and then ratchet around flare nuts, releasing then when your work is done.
The smaller sizes have a rocker pawl clutch for releasing the wrench and line, the larger sizes have a more robust design with double pawl mechanism for added strength.
Fine-tooth gearing means a ratcheting angle of 5°.
Each set comes with 5 sizes of wrenches:
- Metric: 10mm, 12mm, 13mm, 14mm, 18mm
- SAE: 3/8″, 7/16″, 9/16″, 5/8″, 11/16″
Price: ~$82 each set
Buy Now(Metric via Amazon)
Buy Now(SAE via Amazon)
I don’t own any flare nut wrenches, or ratcheting flare nut wrenches, although I have used them before. I suppose the benefit of these, compared to the ratcheting flare nut wrenches that have a pivoting jaw that bends open for access and ratcheting, is that you require less space to actually use the wrench.
Why is there a split down the middle of each wrench’s gripped handle?
These look to be a good effort by Astro Pneumatic to create a semi-unique approach to common automotive fastening needs. I say semi-unique, because I have seen enclosing ratcheting wrenches before.
Here are 2 other Astro Pneumatic innovations we previously posted about:
Wobble head ratchets
3-in-1 hex key sets
If you encounter flare nut wrenches often, what do you think about these new ratcheting wrenches?
You probably know that there are 12 and 6 point flare nut wrenches. Ones with flexing heads, ones specific for AN fittings, crow-rings (flare nut equivalent of a crowfoot) and ratcheting ones that you post about.
I guess they are popular in metric and SAE sizes for auto mechanics. That said – we had a few sets of inch-sized ones from Proto that were very handy when making up lavatory fittings – especially when we had to do hundreds of them in a day on a hi-rise office job. My old inventory says that the Proto part numbers ranged from J3812 to J3832. They did not capture the flare nut like these AP ones do – and the AP wrenches seem like a bit of an innovation – as you say.
There is also a style of crowfoot-type wrench-end that can be wrapped around a flare nut / fitting and torqued with a socket extension bar and a ratchet/breaker bar/t-handle – much like using a crowfoot or a basin wrench.
These seem a bit gimmicky to me.
I’d need to hold one in my hand and fiddle for a bit – test would be to try it out on my 10mm brake lines on both of my toy cars.
Looks like a decent idea but you might give up some access ability with a standard flare nut.
I don’t know i like that pawl and collar release but if it’s smaller than I think it’d be OK.
the handles – comfort? my current set of flare nuts – SK’s.
I don’t know, these seem like they would be a pain in the butt to get on and off . As far as I understand and have used them, flare nut wrenches are made to slip over line connections (ie gas line), they almost ratchet by themselves anyway:
You slip it over the line, then onto the nut, turn the nut, slip it off the nut back onto the line, reset the wrench position, slip it over the nut again, repeat. It goes pretty fast once you get in a rhythm.
mike aka Fazzman
I think id prefer my old school standard ones,these look like you need more room to use/operate. Flare nuts are fairly soft and dont require alot of torque. Flare nuts were pretty common on aircraft back in my military days,we even flared our own tubing.
and then there’s that price for import stuff,no thanks.
Your point about softness is important. They have to be soft in order for the threads to deform and seal. That is why they have their own special wrenches, it is too easy to round off a Flare Nut with an open-ended wrench.
HangFire, I’ve never seen a flare nut designed to seal via the threads. Àll flare fittings I’m aware of, both 37.5° and 45°, form a metal to metal seal at the angled mating surface of the flare.
We used the wrenches less on flared connectors and much more on various sorts of compression connectors and tube/hose fittings. Compression connectors (Swagelok and Hoke were early brands) rely on a ferrule (the Brits call this an Olive) that grips and seals as the fitting is made up. The treaded parts of the fitting are there to pull the ferrule into the body (receiver portion) of the fitting – and compress it to seal against the pipe wall. Just like flare fittings – over-torqueing the compression nut is a no-no.
I should have also mentioned that once a compression fitting has been applied – it is not so easy to remove it as the ferrule has been “compressed” into the wall of the tubing. Most of the time – you just cut it out and re-plumb the job. But sometimes this is impractical – so you might try a a compression sleeve puller. Ones are sold by Pasco (2 different designs – #4661 and #4665) and Superior Tool #03943
I agree with you on that one. I have NEVER seen a flair nut that is supposed to bugger up the threads to seal it up. Metal to metal is how they seal off.
If it was the other way, you wouldn’t have a leaking problem if you have any trash on the mating surfaces
These have the potential of becoming stuck in a few senarios.
I recommend taking a peak at the ratchet handles too, mondo bizarro…. http://www.rarestar.com.tw/html/front/bin/ptlist.phtml?Category=325349
Maybe another source?
These are the ones I have, and they seem to work very well
That’s the kind I’ve used before too. I like ’em, even though the ratcheting mechanism would be less than ideal in any other type of wrench.
Stuart, “I like ’em, even though the ratcheting mechanism would be less than ideal in any other type of wrench.” Please expand on this comment. What other type of wrench are you referencing? And, how is it used on that type of wrench?
I. have only seen this mechanism on a flare nut style wrench. Obviously you have seen are referencing something different.
I think I know what he means. The ratcheting action ‘works’, but you have to be able to swing the wrench to the next flat on the but, as it ratchets from one flat to the next. It is the equivalent of a 6 tooth (per revolution) ratchet for the smaller 6 point wrenches, and 12 for a 12 point. They work great and don’t slip, but need as much swing to use as a breaker bar. It is ki d of neat, though, the way they open up and snap closed over the fitting.
I’m more talking about ratcheting adjustable wrenches and the such, where a lower jaw pivots in a way that always bugs me. The implementation typically looks to introduce higher corner-rounding potential compared to other ratcheting wrench styles.
These (Proto) brand are the ones I had said we used in out plumbing business – particularly to improve productivity on multiple installs on high rise jobs.
Similar ones are made/sold by Armstrong Tools (USA), Beta Tools (Italy), Facom (Taiwan) , and Super Tool (Japan) – probably others too.
In metric sizes – Facom seems to have the broadest range:
I saw this from Pasco:
I have ordered open end ratchet wrench, and i have received close end. how can I can receive the open end, already i had purchased a close wrench.
Have you contacted the seller or place you ordered it from?