Turbine GRM+ Memberand Reader
7/2/22 1:13 p.m.

The rear brake hard lines on my Audi 200 20v are rotten, and I broke one trying to loosen the differential mount this morning. 
I've never attempted to make hard lines, and don't really know where to start. What have you guys used in the past as far as materials/tools/technique goes? Any tips or thoughts would be a huge help. Thanks!

All fittings are m10x1.0, just for reference 

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand PowerDork
7/2/22 1:32 p.m.

nickel/copper lines and a quality flaring tool.  The mastercool is the best, but the Eastwood is a little cheaper and works just as well as long as you're OK with bending the lines on the bench rather than in the car.


7/2/22 2:17 p.m.

These work really well compared to the traditional flare tools


Turbine GRM+ Memberand Reader
7/2/22 6:55 p.m.

Cool! So 3/16 line should play nice with the metric fittings? The mastercool kit looks nice, but $350 is a little more than I wanted to spend. I guess if it's that much better than the alternatives, I can stomach it. Does it bend too or is there a separate tool? 

octavious Dork
7/2/22 7:18 p.m.

I did an all new set of hard lines for an old air cooled VW a few months ago. I used my hands and  the round part of my vise to make bends and turns. I tried one of the hand tube benders from HD or Lowes, and it SUCKED. 

maschinenbau GRM+ Memberand UberDork
7/2/22 7:31 p.m.

In reply to Turbine :

Yes, 3/16 is a standard size and will work with the metric fittings. I use one of the cheap crappy bar style tools. It helps to put the tool in a bench vise so it clamps harder, or the tube might slip from between the bars. Just practice a few times until your flares look nice and symmetric. And don't forget the flare nut before you make your flare! I have one of the simple pliers looking line benders. It was maybe $30 and it's good for 3/16. I also have one with the curved mandrel for larger lines like fuel, but combination of my hands with the plier benders does most of my lines. I second Ni Copp it is awesome to work with, though I prefer the aesthetic of galv steel for my builds. So you're talking less than $100 in tools and supplies to get started. 

I'm doing line work at the bottom of this page of my build thread

GaryC83 Reader
7/3/22 4:05 a.m.

I always make my lines in cheap E36 M3 steel hardlines first before transferring over to stainless hardlines.  I've also found the more expensive compound benders like Nitrous Express' and such work quite well, where they have angles marked on the die and some have different radius dies available. Again, we probably go further than most bother to... but. 


Layout on cheap E36 M3 steel, marking starts of bend radius and the like.  Ignore the existing old hole in the floor. This was an update of an older car to a (then) newer power boosted master.

Transfer that over to stainless hardline, and mount. Done. 


Dusterbd13-michael MegaDork
7/3/22 6:15 a.m.

So, since this thread is here...

Ive got to build all the lines for the race car. I was planning nicopp since its so nice to work with. But its also really soft feeling.

Is there any reason NOT to use nicopp in performance applications? Whats the actual downside to nicopp, other than cost? Ive never seen it used by the oem.

rustomatic Reader
7/3/22 9:01 a.m.

Sometimes, they'll let you go behind the counter at AutoZone or Napa or whatever, where they have many different pre-made lines of varying lengths to get you going.  You can just add your own bends, using your existing lines as a template--always use a bigger device than you think you need (like your knee instead of  your forearm) to make a bend.  Just don't get kinky.

ddavidv UltimaDork
7/4/22 6:45 a.m.

I don't find them too hard to make, and actually sort of like doing it. But my latest project had a lot of complex curves, plus I needed one that ran the length of the car. I wound up ordering new ones from these guys:  https://rpui.com/the-right-stuff/  I also got a new fuel line. Fit was excellent, and I didn't think the price was bad. 

The first fuel line they sent was way too short. Apparently, the had a bad pattern, so I sent my original. They bent one from that at no extra charge. So if you need something not in their catalog I'm betting they could make it for you.

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