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View Full Version : Brake line tube frames- so easy even I can do it



Old Busted Hotness
02-03-08, 07:18 PM
Building a slingshot dragster, Funny Car, or something more exotic? In this case a rock crawler. Styrene just won't cut it for a frame, and brass is too expensive/thin/other objection? Steel is real, boys. Head down to the local auto-parts store and pick up some brake line, bender and tubing cutter (it'll save your Dremel cutoff wheels for more worthy tasks). Then hit up Home Depot for a MAPP torch, brazing rods and you're ready to go.

25 feet of brake line: 20 bucks, give or take. Be sure to get the older (galvanized) stuff, not the new coated brake line. While burning galv is somewhat toxic, if you do it outside you'll be all right. The new stuff is plastic-coated and you'll have to grind it off before you braze.

MAPP torch, extra cylinder and brazing rod: 50 bucks for a decent auto-lighting outfit.

No pics of the in-process, I'm afraid. The flash wrecks the glow of the metal, and anyway I couldn't pry the Mrs away from whatever silliness she's got up to today.

If you can solder, you can braze. It's basically the same process, at a higher temperature.

Bend the tubes into the shape you want (helps to draw it out on paper beforehand) and fishmouth the joints you're going to make. If two tubes cross, cut away half of each one. The idea is to make the joints as tight as possible. If you can wedge the tubes together while brazing, you're ahead of the game. Otherwise, a small Vise-Grip will hold one end of the tube while you braze the other.

Braze on a fireproof surface, like a sheet of steel (not the wife's car, I found that out the hard way). I use a car ramp, the sort you drive up on for oil changes. Don't braze on concrete; it'll explode and throw hot chunks at your head.

Light the torch, and heat both tubes uniformly, until they glow a dull red. Then hold the brazing rod in the flame to heat it as well. Once the tubes are bright orange-yellow, touch the rod to them and continue to heat. You'll see the melted rod wick into the joint. Let it build up a little, then remove the flame. Go round the back and do the other side of the joint.

Then let it cool off, cut some more tubes, and do it again. Once you get the hang of it, you'll enjoy the hell out of it.

http://www.scalemotorcars.com/forum/images/imported/2008/02/14.jpg

I whipped this up in about four hours. It's already strong enough to stand on, and I'm a big boy. Remember, brazing is easy, bending two tubes exactly alike is hard!

Rick
02-04-08, 11:45 AM
Thanks OBH. Thats a good tutorial.

Old Busted Hotness
02-05-08, 08:02 PM
Just to finish it up:

http://www.scalemotorcars.com/forum/images/imported/2008/02/16.jpg (http://img225.imageshack.us/my.php?image=img2827ld6.jpg)

Rick
02-24-08, 05:11 PM
I've been experimenting with brake line tubeing when building a chassis. As OBH mentions, its easy to work with but, a word of caution. I've just been informed that some brake line tube has a galvanized coating that can be VERY poisonous. So, as always, use appropriate eye, nose and mouth protection.

Don Garrett
02-24-08, 05:38 PM
Just buy the stuff that isn't coated....it's easier to work with anyway.

hot ford coupe
02-24-08, 06:00 PM
Thanks Rick, for the warning. The doctor was having a hard time figuring out why my hair, teeth, fingernails and eyebrows fell off. Now I know. Anybody have a Sharpie pen? I hate walking around without eyebrows. 1rolling1 1rolling1 1rolling1

Rick
02-24-08, 07:11 PM
Speaking of Sharpie pens, do you guys know that they are great for giveing parts that red or blue anodized look? Paint the part with the Sharpie and then clear coat it.

Thrillbilly Rich
02-24-08, 07:12 PM
HFP I have a stencil and an Airbrush! Also 'll swing by and get some Press on Nails! We will fix you right up!he1he he1he he1he he1he he1he he1he he1he he1he he1he he1he he1he he1he he1he he1he he1he 1moon1

BrassBuilder
02-24-08, 09:03 PM
Use firebrick for a base for welding. You can get it at the hardware store for 6 bricks for around 10 bucks.
I just lay them out to cover my bench and weld away. If you take a chisel, you can cut them in half/thirds/quarters to use for propping up other pieces.
Mike

Old Busted Hotness
03-01-08, 09:50 PM
Use firebrick for a base for welding. You can get it at the hardware store for 6 bricks for around 10 bucks.
I just lay them out to cover my bench and weld away. If you take a chisel, you can cut them in half/thirds/quarters to use for propping up other pieces.
Mike

I'm a bit more primitive. I use an old car ramp on the garage floor. Sometimes the paint catches fire, but never the same spot twice.


I've been experimenting with brake line tubeing when building a chassis. As OBH mentions, its easy to work with but, a word of caution. I've just been informed that some brake line tube has a galvanized coating that can be VERY poisonous. So, as always, use appropriate eye, nose and mouth protection.

I believe that's a bit of exaggeration. Long-term exposure to galvanized-metal fumes (say an 8-hour shift) will give you a case of Metal Fume Fever, essentially flu-like symptoms and maybe a headache. It'll go away in a day or two.

On the other hand, I'm no expert and have little to no regard for my own safety.


Just buy the stuff that isn't coated....it's easier to work with anyway.

If you can find it. There's apparently a new Federal law mandating plastic coating on all new replacement brake lines, so if you find a source for galvanized or uncoated brakeline, stock up.

Latest project:

http://www.scalemotorcars.com/forum/images/imported/2008/03/1.jpg