Which flare nut wrench set? (size combinations)

[GuidoK]

I'm looking for a flare nut wrench set (open box spanners) but there seems to be 2 types of size combinations in wrenches.
I'm looking for a metric set.

So there are the combinations 8 x 10 mm, 9 x 11 mm, 12 x 13 mm,
14 x 15 mm 16 x 18 mm, 17 x 19 mm
Like this set:
http://www.bgstechnic.com/products/detail/840

But also 8x9, 10x11, 12x13, 14x15, 16x17, 18x19
Like this set:
http://www.bgstechnic.com/products/detail/6103

This is obviously for flare nut combinations consisting of 2 different sizes so that you can always use 2 wrenches from a set.

But which set to get?
It's for use on pipework (brakes, airconditioning) on cars (european cars). I have no idea what the usual common sizes are on couplings etc.

 

[shoggoth80]

I like the second set. When eyeballing, I occasionally guess wrong and it is just the next size up. Easier to flip the wrench over than to go grab a different wrench.
I've run across a lot of 8, 10, 11, 14mm flare nuts. I've also come across 18mm, 19mm, and 21mm on American and Japanese cars (steering boxes/racks). Grab a set, and fill in that last size, and you'd probably be good to go for bit.

 

[GuidoK]

Yes I understand your point but that is not what I meant.

Take for instance this picture:

The nut is a different size than the coupling piece. So you need 2 different sizes. If it was the same size you'd have to have all wrenches twice, always.

But I don't know what the usual size combinations are on (automotive) brake and aircon lines. So that's why they have these size combinations. To prevent having to buy 2 sets.
But probably 1 of the 2 sets us meant to cope with the size combination for my application. but which one?
Or is it always just a mixed bag that differs from manufacturer to manufacturer?

But for estimating size and getting the right wrench first time the second set is indeed better.

 

[Robbie B]

My set is more akin to the first set. I've never had an issue where I needed 2 sizes on the same wrench. Also don't forget crows foot flare nut wrenches. Those saved my **** a few times.

 

[Hiball]

Don't Overthink it...

 

[cowboy73]

For this situation:

 

[bonneyman]

Yes I understand your point but that is not what I meant.

Take for instance this picture:

The nut is a different size than the coupling piece. So you need 2 different sizes. If it was the same size you'd have to have all wrenches twice, always.

But I don't know what the usual size combinations are on (automotive) brake and aircon lines. So that's why they have these size combinations. To prevent having to buy 2 sets.
But probably 1 of the 2 sets us meant to cope with the size combination for my application. but which one?
Or is it always just a mixed bag that differs from manufacturer to manufacturer?

But for estimating size and getting the right wrench first time the second set is indeed better.

Typically, this type of brass fitting in the States is a 7/16" coupler and a 9/16" compression nut. Since the flare wrenches I have are 3/8 x 7/16 and 1/2 x 9/16, the two sizes I need are not on the same wrench. So, I can hold with one and remove with the other.
But on auto connectors, the mm sizes I wouldn't know.

 

[Ramblin Man]

As stated above, use a regular open end on the coupler body. If you put a flare nut wrench on the body, and you get your second nut tightened, you will not be able to get you flare nut wrench off the coupler body.

 

[pistolpete1313]

From my Mercedes, I've used 9, 13 and 17

 

[GuidoK]

you will not be able to get you flare nut wrench off the coupler body.

Yes I know for that typical part.

But I ment more like in a common situation like this:

(didn't want to post this pic to mess up the layout)

Sure I can use a standard wrench in the middle (I can even use standard wrenches all thogether), but I suspect that those 2 sets I pointed out are there to cope with this specific problem, hence my question which of the 2 sets are more likely to be destined to use on cars (brake/steering/aircon).
Or is there a totally different reason to have the 2 sets of size combinations that I haven't thought of?

I may overthink things, but I have a hard time changing the nature of the beast

 

[cowboy73]

Yeah, you are way overthinking it. You really only need one set. I'd get the second one you have listed because the sizes are in 1mm increments on each wrench. Or if you can spare the cash, get both!!!

 

[bonneyman]

As stated above, use a regular open end on the coupler body. If you put a flare nut wrench on the body, and you get your second nut tightened, you will not be able to get you flare nut wrench off the coupler body.

Yeah, that too.

 

[Ramblin Man]

Gotcha O. P. I would get the second set if it were myself making the purchase.

Hope this helps.

 

[Hiball]

I've used open end on brake unions plenty of times, but if it distresses you you can still find some Old school Mac/snappy single sized open/flare wrenches on eBay. I actually prefer those to double sized wrenches, it's nice being able to run threads with lifting on and off the hex.