illmatyk
Well-known member
I'm not too sure if this is the correct part of the forum to put this but, any body have some tips/tricks in making/bending brake lines/tubing?
Will a 1/4" bender be ok with 3/16" line?
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Be shure to cut the Lines with a Pipe cutter, a saw will not make a clean enough cut for flaring.
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Is not a question of picking between double-flare and bubble. You don't get to choose.Regarding the line ends, I would go double flare unless you have money for the Mastercool bubble flair kit.
Thanks, will read through this.I don't know if it will help you at all, but here's a link to a post on my blog about when I did the brake lines on my BMW Isetta. Hard lines are fairly cheap, so it doesn't hurt to get an extra one to practice bending with.
http://bzisettas.blogspot.com/2011/05/isetta-brake-lines.html

Thanks for these tips! using coat hanger to make a prototype never crossed my mind!
- Use a tubing bender. Yes, you can do it bare-handed, but it's slow, prone to failure, and you just can't make precise, tight bends.
- 2 - Make a prototype using coat hanger wire first.
- 3 - Make sure you instlal your tube nuts BEFORE you flare then ends!
- 4 - Make sure yout tube nut doesn't get trapped in the middle of the line by a bend. (I've don this more times than I can count -- I install a tube nut, make a bend, then discover the tube nut can't get past the bend to the end of the line.)
- Buy quality tubing. I like Bundyweld myself. There's a lot of crappy tubing out there that splits when you try to flare it.
- Use the proper flare at the end. This means either double-flare (SAE,) or bubble-flare (ISO). Single-flare WILL leak.
- Avoid over-torqueing the tube nuts. For a fresh flare, you don't need a lot of torque to get the fitting to seal.
- When all else fails, send your coat-hanger prototype to Classic Tubing and they will make the line for you.


It will distort and squash the line a bit in the bend. Whether that's acceptable us up to you, but I wouldn't use it. When it comes to brake plumbing, in my opinion, its either perfect, or junk.
I use this bender:
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It has a mandrel accommodating various tubing diameters.
I have a set of these, they work great.
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Also, anybody have any experience with this kit:
http://www.tooltopia.com/kd-tools-41590.aspx
I'm thinking of ordering this kit as I don't have a flaring tool of my own( currently borrowing from a friend ).
after using all these cheap flare kits i got real tired of them. ended up buying this one http://www.eastwood.com/professional-brake-tubing-flaring-tool.html and love it. perfect flare each time. being that they are brake lines i wanted it perfect. i use 3 different benders depending on what i am working on from the ones above to a simple pice of tube to bend coils
You entirely get to chose if you are making a brake system. You can pick either all SAE or all Bubble. Or mix and match, which I do not think is a good idea. My point was, however, that double is far far cheaper. A decent double flare is <$100 while a decent bubble is ~$350. I am of course well aware they do not interchange, but maybe I should have mentioned that when I said pick one.Is not a question of picking between double-flare and bubble. You don't get to choose.
Double-flares are used on SAE fittings, which use imperial measurements (1/2", 5./8", etc...) Bubble flares are used on ISO fittings which use metric measurements.
However, you can run into oddball fittings, especially on cars, that mix the two standards (bubble flares on imperial fittings and double-flared fittings on metric fittings.) Manufacturers mix and match this stuff to keep the wrong parts from being installed on the assembly line (Ford did this on the '93 Cobra R, since the Cobra R got a unique master cylinder.)
So make sure the flare's style is correct for the fitting. Double-flare and bubble are not interchangeable.
It will distort and squash the line a bit in the bend. Whether that's acceptable us up to you, but I wouldn't use it. When it comes to brake plumbing, in my opinion, its either perfect, or junk.
I use this bender:
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It has a mandrel accommodating various tubing diameters.
For tighter bends less than 90-degrees, I use this:
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I got mine from Eastwood, but Harbor Freight has these on clearance right now.

i don't like roll line because its hard to straighten just to rebend, so i use straight line and flare unions, then reflare when done.
Sorry Nutts, but these are the kind of bends you get when you either use the wrong tool or don't use it properly. I'm sure the lines work just fine but it's certainly not professional in appearance.
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For tighter bends less than 90-degrees, I use this:
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I got mine from Eastwood, but Harbor Freight has these on clearance right now.
You figure the fluid knows the difference?It will distort and squash the line a bit in the bend. Whether that's acceptable us up to you, but I wouldn't use it. When it comes to brake plumbing, in my opinion, its either perfect, or junk.
I have one of these and I'm ready to give it away. The finish was terrible, and it kinks the end of the tube every time you use it.
You figure the fluid knows the difference?
Thousands of dumb shits put brake lines on every day with less than perfect methods, they do seem to work.