I have a few different varities of bubble flaring tools, but using the back of the bar with a double flare die doesn't guarantee a flare, the bubble flare tools have a die that threads into the tool and prevents rocking as its cinched down.


The double flare die sits free and rocks too easy and eventually makes a bad flare.


The short sections being sold at parts stores make repairs very easy for a diy person.

Your recommendation of not fully forming the bubble on the tool is top notch, the actual flare mating face will be done when its screwed into the female fitting.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)