All automotive fittings are a 45-degree double flare. NOT 37-degree flares, such as A/N fittings.
Actually, that is not true. Most newer cars use the ISo Metric flare, more commonly know ans the "Bubble Flare". It kind of looks like a 1/2 finished 45 degree, but most definetly is not. while this doesn't really apply too much to our old 'Bolts, it can come up, especially to those among us that are using late model parts in the brake system. If the incorrect flare is used, the fitting will most definetly leak. so make sure that you properly ID the fitting that any doner parts use, late F-Body and S trucks are ones that can have the ISO type flare.
Anyone needing a good instruction on how to properly flare brake lines, check out my Webshots album. I beleive the Denny also has a demonstration in his, only using the Fed-Hill flaring tool instead of the Snap-On tool that I used.
I would also like to ention, I work prefessionally as a brake/alignment mechanic, and re-use the brass all the time. never had one leak, exept in cases where the threads were bunged up.
