Brake lines how-to?

[tog]

I posted this on the BMW forum but don't seem to be getting any response... since I'm a Porsche guy from way back and am more familiar with this forum anyway (most of my previous posts are here) and since this would apply to Porsches anyway thought I'd try here since I know you guys will have the answer..................................

I need to fabricate some brake lines for my restoration of a 1987 BMW 325e (for the wife -- I remain 911-nuts) only. The long convoluted lines (especially to the rear) are too difficult to locate, buy, ship and way to difficult to put in place as one solid continuous line. So I'm going to fabricate some shorter pieces to put in in place of the long one-piece line and fabricate some of the shorter ones or maybe just buy some of the shorter ones -- anyway......

I have all the tools necessary to do the job(turns out I might be wrong on that -- I have a "double flare" tool -- I probably need a "bubble-flare" tool? -from Pelican- see below). Just need to pickup some tubing and fittings. What are the official size/designation for the lines and fittings I need to tell my local parts guy. (All I seem to find info on is English sizes not metric ones -- they can't possibly be interchangeable). I've seen acronyms like "AN", "NPT" and various sizes that seem to be only in English sizes and would like to pickup an economical combo kit on-line or get it piece-meal from the local parts guys -- but need to know what I'm looking for acronym-wise.

Stainless steel lines appear to be 3.0mm ID and 5.0mm OD. Fittings appear to be 1.0 thread and about 11mm total diameter. Old fittings took an 11mm wrench for the male fittings with a 14mm wrench on the female (rubber lines -- these I'll be purchasing from Pelican). Anybody know the right acronym/size I need?

Also, a little more research reveals that the flare appears to be a bubble-flare versus the normal double-flare -- I have a double-flare tool -- anybody know where I can pick up an "economical" bubble flair tool? -- the $370 kit doesn't make economic sense for just a few bubble flares.

...............................THEN I ADDED....................................

What... no brake experts out there? a bimmer bummer .......

OK.... I found an economical tool that will do "metric ISO bubble flare" -- is that what I need? ..............Ah, finally found the same one at Pelican (item# TOL-OTC4504) at $20.22 (cheaper thatn the other seller )-- missed it somehow the first time around. It has 4 dies: 4.75mm ('3/16" tubing' -- other tool seller had this notation), 6mm, 8mm, and 10mm -- do I presume I have brake lines that are 4.5mm and that 3/16" tubing is compatible if that is all I can find? (3/16in. works out to 4.7625mm so seems to be the same? Whipping out my Porsche dial calipers puts the busted lines at 4.79mm average of the OD so does that mean that brake lines are measured by the OD? -- since it is very close to the 4.75mm die size)

Does Pelican have brake lines and fittings? -- I can't seem to figure how to find that if they do.

If anybody knows the answer to these questions I'd appreciate a quick reply -- I need to get this BMW restoration project moving and I've got a big order I need to get into Pelican as soon as I can figure out what brake tools, lines, fittings I need to add to it -- THANKS !

...............................THEN I ADDED MORE....................................

OK, managed to piece this image together from the internet -- difference between double flare and bubble flare -- and the lines I managed to pull of the BMW (that I didn't wreck what with all the rust and all) seem to look like the bubble flare.


THANKS,
Terry O

[JP911]

A good auto parts store should have Euro, English, Japanese, etc. brake lines with pre-fabbed flares and fittings. I had to fab some lines for my 930 brakes, so I just took the soft lines to the parts store and tried several different fittings with bubble flares until I found the right match. You could do the same and then cut the fittings off and use them on your new lines you plan to make. The short lines I purchased were under $5 each, so it's a pretty affordable way to go.

[KFC911]

I did the same as Jon for my 930 brake conversion. I used two that were the standard 12", and one that was 30" in length with the fittings already attached. All of the auto parts stores in my area have them and I found the color of the lines/fittings varied from store to store. I found some closer to my car's original lines color rather than "bright & shiney" but don't recall which store (NAPA, AutoZone, etc.).

[tog]

JP,

That's a thought -- but I have a predisposition to buying collections of things I need so that the next time I need them they're already sitting in my garage on my parts shelf (yeah, my garage is way overloaded with stuff but that's the fun of going in there -- I never know what I might whip up next from all the spare stuff I have )

Anyway... what I'm looking for is the right size/acronym so I can buy a collection of spares for this BMW and some Porsche projects.. lots of internet places sell collections of lines and fittings (if Pelican doesn't have it) -- I just need to know what I need -- I've pieced together an example of the various assortments that can be had in the attached jpg -- just need to know which I need.

Thanks,
Terry

[tog]

Also, It occurs to me since I measured the threads (with my thread reader from the tap & die kits I have) that the fittings I could salvage seem to be 1.0 mm and since there are 24.5 mm to the inch, does that mean I need to use fittings marked as "24 thread" ?

[tog]

OK, so guessing that what I need is 3/16" tubing (= 4.75 mm?)with fittings that are 24 thread and (since the fittings I'm trying to match takes an 11mm wrench) I need 11mm. Doesn't seem to exist in the chart above. So where do I get such things or do I have this all wrong?.......... Any experts out there?