How to make tight bends in tube without kinking?

[davepl]

Today all my new hardline material should arrive... I need to do all new brake and fuel lines. The brakes are a mix of 1/4 and 3/16, and the fuel is 3/8.

I ordered stainless so it'll stay looking nice. But in looking at my originals there are a couple of places (like right where the hard line goes to rubber to connect to the fuel pump) where they've got a really tight bend. 3/8 line doubles around in a 180-degree turn with a radius of about 2 inches in one place.

I don't know if the factory used a mandrel, or how they got it that tight. Are there are tips or tricks anyone knows to make a tight bend like that without kinking the tubing?

I've seen tubing with a spring outer wrapper, and I could try to find the spring part and use it just during bending, but not sure if that'd help. I could in theory do it without those tight bends, but I'd like to keep it as close to original as possible.

If you're curious, none of the vendors nor inline tube or classic tube has them for big-block long-horn 3/4 tons, so I'm sort of on my own with this one.

Dave

[Dunenutt]

These work very well, and bend stainless like butter.

http://www.swagelok.com/search/find_...9-501f774bb60d

Eastwood or some of the other places may have a cheaper version.

[wilbilt]

The springs work to some extent. Tight bends are iffy.

I have heard that filling/packing the line with fine sand can help achieve a tight bend, but I haven't tried it.

[davepl]

Originally Posted by wilbilt

The springs work to some extent. Tight bends are iffy.

I have heard that filling/packing the line with fine sand can help achieve a tight bend, but I haven't tried it.

I was reading a thread on MotoIQ that suggested the sand or baking soda, but no one could seem to figure out how to get it packed in tight enough to do any good. I've seen it done for larger tube, like 3/4, but they packed the tube with sand and then welded the ends shut for the bend...

[vidman]

If you have a good hand tube bender you can make bends as small as the bender will allow. if i remember right you have to use a 39 degree double flair but someone that bends tube for a living will correct me if i,m wrong..

[AusTx68]

What about using a 90 degree fitting screwed into the fuel pump with a 3/8 barb on the inlet side. I did something similar when I went all SS with -6 AN hose and fittings.

[GASoline71]

I got this tubing bender off a Mac Tools truck... It bends EZPZ up to 180 degree bends in 1/4" to 1/2" tube. Just happens to be in the same pic as my Flaring Tool Kit.



I made this 3/8" pump to carb fuel line with it...



Gary

[terry b]

Nice job man.

[bollybib]

I should keep an eye out for a Mac Tools truck.

[bobs409]

Originally Posted by davepl

I've seen tubing with a spring outer wrapper, and I could try to find the spring part and use it just during bending, but not sure if that'd help. Dave

That's not for bending purposes, it's actually called gravel guard to help protect the line. I buy that in bulk from http://www.classictube.com/

I got all my line, fittings and gravel guard from them for my wrecker project and made my own lines.

[GRX]

Originally Posted by wilbilt

The springs work to some extent. Tight bends are iffy.

I have heard that filling/packing the line with fine sand can help achieve a tight bend, but I haven't tried it.

Originally Posted by davepl

I was reading a thread on MotoIQ that suggested the sand or baking soda, but no one could seem to figure out how to get it packed in tight enough to do any good. I've seen it done for larger tube, like 3/4, but they packed the tube with sand and then welded the ends shut for the bend...

Glass bead works well for this trick. Smallest I have done is 1/4" tubing. The trick is to make sure both the bead and inside of the tubing is clean & dry.

[tex_waco_usmc]

I did all my bending with a hand bender that I bought at the local parts store for like $15 and just bent it slow and controlled, never forced anything and it went great without any issues! All my tubes are inline SS tubes!

[El Campo]

Thats a nice bender that Gasoline71 has up. I have one of those Eastwood bending pliers and made a 180 that had only a 1 inch radius without kinking. I hope you have a darn good flaring tool! I broke the 1/4" die on even a Rigid 45 degree double flaring tool on the first flare before breaking down and buying a Mastercool hydraulic flaring tool. Stainless is a whole different animal than other materials. Incidentally if you do not have the right tools I will rent you my Mastercool which I have the 45 degree double flare attachments as well as all the 37 degree single AND double flares for also. Plus I have the cutter to cut stainless and all my different benders too. If that helps you out.

[davepl]

I have the Mastercool (I think it's also sold at Matco and a couple of other brand names, same tool) hydraulic flaring too. I also picked up the 37 degree dies and cone so I can do AN style stuff on other projects.

If you're making more than one tube in your lifetime, I heartily encourage anyone to get the Mastercool hydraulic flaring tool. I always struggled, especially with larger diameter steel or stainless. With the hydraulic unit I've never failed to make a great fitting, unless I tried something goofy.

[Classic Heartbeat]

In-line tube will bend you up a set of lines. The only difference in a longhorn brake line kit and that standard 3/4ton kit for a 2WD truck with leaf spring rear end is the length of the brake line that runs from front to rear of the truck. You send them your original and they will duplicate it. Then they will have an original pattern for future trucks.... WES

[davepl]

They didn't seem interested, just told me they didn't really have anything for Longhorns, and it took two months to get that answer.

According to their parts listing they have a complete front brake line set for the 3/4 ton, but under their Master Cylinder lines, which are the hard ones, nothing for 3/4 ton.