Annealing Stainless Fuel Line

BBShark

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I bought a preformed stainless fuel line and tried to cut off the hose end and flare it for an AN fitting. That stuff is rock hard! I can't even get the clamp to grab the tube, it just pushes back out. If I did flare it, I'm guessing it would crack.

So I went online to find annealing methods for SS. I found something that, in general describes three different processes but not a "how too". Anyone done this?

http://www.azom.com/article.aspx?ArticleID=1141
 
Pardon ME, but over the decades I have replaced BRAKE lines with a much higher line pressures, to the rear and front and never used stainless or anything that tough and UNworkable....as in WHY BOTHER???

just cause you CAN?? shit, my rear brakes on the vette had the OEM line blow some years ago....bought two ~5" lengths of brake line, and a inline coupling, and so had to cut to length, double flare the end and it's still in use today, same as many another car over the years....

stainless?? WHY?? show car?? what racing body demands that??


I fail to see the need for the aggravation.....

:sos::stirpot:
 
LOL

Larry, did you buy stailess line for brakes? That usually come as annealed tubing. I would not try heating it and experiment with it because well...brakes are kind of important LOL

Even double flaring annealed is a PITA and it probably will crack. A solution will be to make sure it's seamless tubing and then use a 37deg. flare tool so you have an increased sealing surace and a seperate flare sleeve and nut. This will allow you to use a single flare instead.
 
Marck, No it's one of those preformed fuel lines. I havent checked but maybe it's softer wher it hasn't been bent. Maybe I'll try on a straight section.

I'm not sure but I think it's seamless so I should be OK with a single flare right?
 
It'll crack if you try to flare it at room temperature.

I agree with the article you posted, put it in your forming tool (hopefully it's not a hydraulic one), heat the tube to orange (1080 degrees), then flare and let it cool to air temperature naturally. It shouldn't take huge effort to form it. Once it's cooled, take a steel or brass brush and clean the scale off. Use scotch brite on the outside to make it shiny.

Do be careful to keep oil and stuff off your forming dies because that'll push impurities into the stainless.
 
woops, fuel line... my bad.

I have single flared fuel line, no problem. Did use 37 deg. flares. Check the inside of the tubing to see if there's a seam should be clearly visible.

Summit sells annealed line it flares just fine @ room temp. Do need a quality tool like an imperial eastman one.
 
stainless?? WHY?? show car?? what racing body demands that??

Dot 3 brake fluid absorbs water and will start to rust out steel brake lines. When I removed the brake lines from my 68 Corvette, they were about 35 years old. The interior was lined with a reddish brown goo, which I'd say is rust. So stainless buys you rust resistance, especially on the interior where you can't see the rust beginning.
...........................................
For double flaring stainless steel lines, I've sent my lines off to a tubing company. I've used In-Line Tube in Michigan. I had them shorten and double flare stainless steel lines from the rear caliper to the trailing arm flex hose. The lines had to be shortened to fit the Stainless Steel Brake Corporation aluminum calipers.
 
stainless?? WHY?? show car?? what racing body demands that??

Dot 3 brake fluid absorbs water and will start to rust out steel brake lines. When I removed the brake lines from my 68 Corvette, they were about 35 years old. The interior was lined with a reddish brown goo, which I'd say is rust. So stainless buys you rust resistance, especially on the interior where you can't see the rust beginning.
...........................................
For double flaring stainless steel lines, I've sent my lines off to a tubing company. I've used In-Line Tube in Michigan. I had them shorten and double flare stainless steel lines from the rear caliper to the trailing arm flex hose. The lines had to be shortened to fit the Stainless Steel Brake Corporation aluminum calipers.

some people think that brake fluid never needs to be changed.... not a good way to preserve long life and health IMO; but it's pretty common.
 
stainless?? WHY?? show car?? what racing body demands that??

Dot 3 brake fluid absorbs water and will start to rust out steel brake lines. When I removed the brake lines from my 68 Corvette, they were about 35 years old. The interior was lined with a reddish brown goo, which I'd say is rust. So stainless buys you rust resistance, especially on the interior where you can't see the rust beginning.
...........................................
For double flaring stainless steel lines, I've sent my lines off to a tubing company. I've used In-Line Tube in Michigan. I had them shorten and double flare stainless steel lines from the rear caliper to the trailing arm flex hose. The lines had to be shortened to fit the Stainless Steel Brake Corporation aluminum calipers.

some people think that brake fluid never needs to be changed.... not a good way to preserve long life and health IMO; but it's pretty common.

OH, shoot, I forgot, I have used DOT 5 fluid for years now....in all my cars, my vette did pop the rear main line under the driver's door, but it's the only car to do that to me, DOT 5 of course will not rust....

and I hear many a dislike over it, and can't see/understand why....been in my '72 here for 18 years now....:beer:
 
stainless?? WHY?? show car?? what racing body demands that??

Dot 3 brake fluid absorbs water and will start to rust out steel brake lines. When I removed the brake lines from my 68 Corvette, they were about 35 years old. The interior was lined with a reddish brown goo, which I'd say is rust. So stainless buys you rust resistance, especially on the interior where you can't see the rust beginning.
...........................................
For double flaring stainless steel lines, I've sent my lines off to a tubing company. I've used In-Line Tube in Michigan. I had them shorten and double flare stainless steel lines from the rear caliper to the trailing arm flex hose. The lines had to be shortened to fit the Stainless Steel Brake Corporation aluminum calipers.

some people think that brake fluid never needs to be changed.... not a good way to preserve long life and health IMO; but it's pretty common.

OH, shoot, I forgot, I have used DOT 5 fluid for years now....in all my cars, my vette did pop the rear main line under the driver's door, but it's the only car to do that to me, DOT 5 of course will not rust....

and I hear many a dislike over it, and can't see/understand why....been in my '72 here for 18 years now....:beer:

I never personally used it, but I hear that DOT 5 is a bitch to get the air out.
 
stainless?? WHY?? show car?? what racing body demands that??

Dot 3 brake fluid absorbs water and will start to rust out steel brake lines. When I removed the brake lines from my 68 Corvette, they were about 35 years old. The interior was lined with a reddish brown goo, which I'd say is rust. So stainless buys you rust resistance, especially on the interior where you can't see the rust beginning.
...........................................
For double flaring stainless steel lines, I've sent my lines off to a tubing company. I've used In-Line Tube in Michigan. I had them shorten and double flare stainless steel lines from the rear caliper to the trailing arm flex hose. The lines had to be shortened to fit the Stainless Steel Brake Corporation aluminum calipers.

some people think that brake fluid never needs to be changed.... not a good way to preserve long life and health IMO; but it's pretty common.

OH, shoot, I forgot, I have used DOT 5 fluid for years now....in all my cars, my vette did pop the rear main line under the driver's door, but it's the only car to do that to me, DOT 5 of course will not rust....

and I hear many a dislike over it, and can't see/understand why....been in my '72 here for 18 years now....:beer:

I never personally used it, but I hear that DOT 5 is a bitch to get the air out.

Yeh, heard that alot too, never an issue for me, dunno....I suspect the BS about it being softer pedal has to be related to that 'air' problem....only thing that maybe related to the DOT5 was I had a brake hose collapse and fry a rotor/pads/pistons/seals on the left front, but replace all the hoses, front rotors, and rebuilt calipers.....been years now....

:smash::)
 
I have a preformed set of SS brake lines on the '79 and it was not THAT much more expensive than mild steel tubing ... it's been 7 years and the lines have performed trouble free and they're not rusted :)
I had to "correct" a few bends and that material was easy to work with, wouldn't say it was hard or brittle....

I also bought SS tubing from Summit for fuel lines - again that stuff was easy to work with - not as easy as aluminum tubing but definitely workable.... I flared it for tubing nuts and had no issues with the $40 flaring tool that i bought... but I agree with Larry, the clamping force on the tube is marginal when you flare it. Edit: I did not double flare the tube, just a standard 37 degree flare for AN fitting ... I can see double flares being a lot more difficult with SS.....

I am going to use SS tubing for the fuel line on my VW, that line runs thru the center frame tube so i want to make sure I install it once and never have to see it ever again.... I like stainless :smash:
 
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Most stainless is not heat treatable for hardening. An easy test to see if you have heat treatable stainless would be to see if a magnate sticks to it. If it does, it's probably 400 series a ferrous material. Used in tools often, such as dial calipers and mics. Drawing back any steel is pretty easy, heating and letting cool slowly. However I'm with TT, I don't think I would be playing with brake lines.

Stainless is a bitch to cut it's not that it's hard, it's tough! Stainless has a high yield strength it doesn't shear easy. It needs a very sharp tool, but it generates a lot of heat. So then the heat breaks the tool down.

Ralphy
 
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Well it appears that in between the bends the tube is not hard (but still harder than the annealed SS tube I have used). So it might be possible to form a single flare on it. The bad news is that it is not seamless. Not sure but can't I use those soft aluminum seats with this?
 
"those soft aluminum seats".... uhhh, you lost me

if you're talking AN fittings, then yes, you need at least one surface that will conform to the stainless. Trying to get stainless compression - sealled fittings to seal to each other is not an easy task.

stainless is hard because it's alloyed with nickel.

To cut stainless, either abrasives or slow down with you tool steel.
To drill, I love watching noobs working on stainless. They put their drill on "high" and try to force their way through stainless. All that does is burn up drill bits. With stainless, as much pressure as you can safely put on the bit, and varied slow speed will cut its way through.

And just for the record, I've never used a stainless tube that was seamless.... I'm sure they're out there, but I've not seen it.
 
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