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Need help flaring stainless steel brake lines

  • Thread starter Thread starter 66coupe351
  • Start date Start date Dec 5, 2005
6

66coupe351

Founding Member
Aug 24, 2001
84
0
0
Los Angeles, CA
Dec 5, 2005
#1
  • Dec 5, 2005
  • #1
First off I'm confused about what type of flare I need. I started off thinking I would need a 45 degree double flare, but now think I may need a 37 degree single flare. I'm trying to plumb up my master cylinder and combination valve.

I tried making a couple of 45 degree double flares in the stainless tubing I have and completely screwed it up. The tubing was very tough to flair, and it ended up deforming un-evenly and being useless.

Do I need to be making 37 degree single flares? Will they match up properly to my Master Cylinder, etc?
Will I be able to use the fittings I already bought?: 3/8-24 - SAE - 3/16" Diameter
 

302 coupe

Founding Member
Mar 2, 2000
1,952
3
36
Macon, Ga.
Dec 5, 2005
#2
  • Dec 5, 2005
  • #2
AN fittings are 37, you need 45 dbl flares. Stainless steel is tough stuff, I wouldn't try to flare it with a home flaring tool. Its hard enough to flare regular steel tubing properly. You could maybe call some industrial hose/plumbing stores and see if they can make flares for you, probably wouldn't cost much.
 

thehueypilot

Active Member
Feb 25, 2004
1,084
0
37
Medina,Tennessee
Dec 5, 2005
#3
  • Dec 5, 2005
  • #3
You can have it annealed to make it easier to double flare, and a very good flaring tool is a must.
 

HistoricMustang

Active Member
Apr 11, 2003
2,359
0
46
Confederate States of America
Dec 5, 2005
#4
  • Dec 5, 2005
  • #4
302 coupe said:
AN fittings are 37, you need 45 dbl flares. Stainless steel is tough stuff, I wouldn't try to flare it with a home flaring tool. Its hard enough to flare regular steel tubing properly. You could maybe call some industrial hose/plumbing stores and see if they can make flares for you, probably wouldn't cost much.
Click to expand...

.............and SS cracks easy.

HistoricMustang
www.historicmustang.com
 
6

66coupe351

Founding Member
Aug 24, 2001
84
0
0
Los Angeles, CA
Dec 5, 2005
#5
  • Dec 5, 2005
  • #5
Thanks for the replies.

So, I have to go with a 45 degree double flare to match up correctly with everything else?

A 37 degree single flare is always for an AN fitting? Is the threaded fitting that slips over the tubing what makes it an AN fitting, or is it the shape of the item the tube is connecting to? Could I do 37 degree single flares with different fittings and connect it to a standard Master Cylinder?

What is annealing?

Any idea where I could have the flaring done? Custom car shop? Industrial tubing manufacturer?
 
T

tylerrocks

New Member
Oct 13, 2005
514
0
0
Big Spring, TX
Dec 5, 2005
#6
  • Dec 5, 2005
  • #6
FLARE IT YOURSELF! I did with SS. The key is HEAT!!! a ciggarette lighter will do wonders. Get it nice and hot, then screw the punch down. You should be able to feel if it's hot enough.

Tyler
 

thehueypilot

Active Member
Feb 25, 2004
1,084
0
37
Medina,Tennessee
Dec 5, 2005
#7
  • Dec 5, 2005
  • #7
Annealing will reduce the hardness of the material. To double flare SS tubing you need a flare tool like this: http://eastwood.com/shopping/produc...2489&itemType=PRODUCT&RS=1&keyword=flare+tool
 
6

66coupe351

Founding Member
Aug 24, 2001
84
0
0
Los Angeles, CA
Dec 5, 2005
#8
  • Dec 5, 2005
  • #8
I may have to try heat, or get myself a nice tool. I think I have a cheap-o $30 flaring tool right now.

But, again, which type of flare do I need to go with? Always single 37 degree flare for stainless? And what determines the type of flare: the material, the fittings, or the object you are attaching to?

Even that nice flaring tool says it:
Produces single flares 45 & 37 degrees in soft metal & stainless steel lines, and produces 45 degree double flares in soft metal & steel.
So it won't do a double flare in stainless steel? I'm a little confused about their reference to 'soft metal and stainless steel' at one point, and 'soft metal and steel' at another.
 

68keyblr

20+ Year Stangneter
Mar 17, 2003
946
20
49
Arizona
Dec 5, 2005
#9
  • Dec 5, 2005
  • #9
Chop Cut Rebuild

I just happen to be wathching Chop Cut Rebuild today and they said that you don't need double flares with SS lines because Stainless is so strong. Take that for what it's worth.

I personally double flared my lines with a tool I rented from Autozone. Turned out fine, no leaks.
 

thehueypilot

Active Member
Feb 25, 2004
1,084
0
37
Medina,Tennessee
Dec 5, 2005
#10
  • Dec 5, 2005
  • #10
I have that tool and it can do double flares on SS seamless "annealed" tubing. A double flare is used in all brake lines. A single flare can crack/split and cause loss of brake pressure. SS can be very hard and very brittle. It may be cheaper/easier for you to buy pre-bent SS brake lines.
 
6

66coupe351

Founding Member
Aug 24, 2001
84
0
0
Los Angeles, CA
Dec 6, 2005
#11
  • Dec 6, 2005
  • #11
Thanks again for the replies. I'll check out my local auto parts store to see if they have a brake flaring rental tool that works better than the basic one I have.

I bought all new factory SS tubing, but have a few custom finishing pieces I need to make.

I'm Installing a dual-bowl MC, brake booster and a combination valve, so I just have to make three short pieces to finish plumbing the area near the MC.
 

65-347

New Member
Nov 13, 2005
39
0
0
Illinois
Dec 6, 2005
#12
  • Dec 6, 2005
  • #12
Stainless does not get double flared, the end of the flare will split and break (if you don't break the flare tool first) you need AN 37-degree fittings. Look up Pure Choice (520-505-8355) or Stainless Steel Brakes www.ssbrakes.com for help.
 
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