I would like to run stainless hardline for the brake system. I'm thinking 3/16" OD (-3) tube should be used. My question is what wall thickness should I get? Bright, anneled (sp) 304 s.s tube with a 0.023" wall comes to mind. Am I on the right track here?

Thanks in advance

To be honest I don't remember the wall thickness I have used...

It most defiantly must be annealed or you won't be able to flare it.

It also makes things easier if you use a hack saw to cut the tubing and a file to square up the end because a tubing cutter will cold work the metal making flaring it harder (and you will be more likely to split it). A small chamfer on the inside and outside also helps when flaring it.

Going by your location just head over to McKenzies. They are good guys and will hook you up with all the right stuff.

McKenzies Performance Pro
(714) 441-1212
2366 E Orangethorpe Ave
Anaheim, CA 92806

Thanks for the response. I'm right around the corner from them. I might stop by. I do lots of hardline stuff but mostly fuel and nitrous systems. But comming from a preformance marine background I've never done it for brake systems yet. I buy nuts and sleeves by the 1,000's so I'm good to go there. I just want to be sure the wall thickness is correct before I order the tube.

Bending tube is fun. I can't wait to get rolling on this project. Here's a regulator set up I did last night.

I've heard that getting stainless flare fittings to seal good is challenging, but it looks as though you've worked with it enough to know what you're getting into.

The regulator tubing looks great!

I purchased some 3/16" SS tubing from one of our instrument vendors here at work, it was .035" wall thickness. I would use nothing less than that for brake lines. Are you going to use AN fittings? If you are you will have to get a 37 degree flaring tool. Personally I would not use the annealed version. I bought a Rigid 37 degree flare tool and it does the flare just fine on the hard SS. A cheap flaring tool will not work however.

Vince

You have to use annealed tube or else you can't bend it.
Ridged flaring tools are ok but I'll stick with my Papco. I also have a hand held deal made by Parker that works very well. I like it over the Ridged because the die's are not as thick. I can do back to back flares in 3/8 tube that are only 1 3/4" long with the Parker set up and still have room for the nuts and sleeves.

Anyway I just ordered some 0.035 wall seemless tube. Once I get into it I'll post some pics if there is any intrest.

[QUOTE=superdave013]You have to use annealed tube or else you can't bend it.
QUOTE]

That is certainly news to me, cause I just re plumbed my 34 project because of a M/C switch and it is all hard drawn 3/16" seamless .035 wall thickness SS that I bent with my hand held Imperial bender. 1/8", 1/4", 3/8", and 1/2" hard SS tubing is bent all day long by instrument techs at the chemical unit I work in.

Who in the world told you cannot bend non annealed tubing?

Are you using standard 45 degree DOT fittings, or AN 37 degree fittings?

Vince

I'm using 37 degree just like the ones in the pic I posted above. I'm in the AN fitting biz so hardline is just a natural extension for me. I bend up something everyday but like I said, always other applications other then brakes.

You act like annealed stainless is like annealed copper. It's not even close and is still very stout. If I handed you a piece of it you would never know if it is annealed or not unless you looked up the part number. It flares really nice and does not oval as much when bent. I bet if you grab that regulator in the pic above and give it a yank the fittings break off before the tube bends. lol

It's just that I've always used bright, seamless annealed 304 tube in the past. But hey, I'm always up to learn so I'll grab a piece and try it out.

And before you ask. Yes, my flaring tools are 37 degree.

BTW, if they are using compression style fitting like Swagelok, Parker or Gylok in your chem plant the tube needs to be softer then the fittings. Ask your techs about that. As a matter O fact Swagelock suggested ordering information calls out for fully annealed, high-quality (type 304, 316, ect) (seamless or welded and drawn) stainless steel hydraulic tubing ASTM A269 or A213 or equivalent. Hardness 80 HRB (180 HV) or less.
It says 3/16" 0.028 wall is good for 5,400 psi and 0.035 is good for 7,000. I guess I'm overkilling it by using the 0.035 wall.

Some good reading on the Swagelok site but it's hard to find. Here's a link for ya. http://www.swagelok.com/downloads/w...N/MS-01-107.pdf

I bent tubing for industrial instrumentation for 16 years myself.

Don't know where you got that, never said it. I just know that it is not allowed in the aircraft industry.

I still do not understand your statement about not being able to bend non annealed.

Have a good one
Vince

Swagelok does not recommend it. Their standard instrumentation tubing is annealed ASTM A213. What is the manufacture and part number of the tube you used? I have most everyones specs right here. I'll look it up and see just what it is. You might be in for a supprise.

What's your source on the not allowed in the aircraft industry? That would be news to me but hey, would not be the first time. These guys sell annealed s.s. tube for airplanes. http://www.wicksaircraft.com/catalo...1835/index.html So does aircraft spruce and their price is way better to boot.

Anyway this has been a fun first thread for me. I did learn some things. 3/16 s.s. 304 tube with a 0.028 wall is good for 5,400 PSI. I have the DOT approved Brake Quip hose crimping system and it's test station only tests the hoses to 3,000 psi. But I am glad I went with the thicker wall anyway. In the past I've found the flares turn out a little better with the thicker stuff.

You have a nice day to man, was nice chatting with ya.