I'm trying to fabricate a header for an AP .061. I'm using slightly bigger than 1/4" aluminum tubing. I'm having troubles getting it to bend without kinking or tearing. Any ideas?

Melt some lead and fill the tube.

Bend the tube around a half moon [ groove the same dia. as tube ] mandrel

Melt the lead out of the tube.

Fill with water, freeze, bend and let ice melt. Pack with sand, bend, empty out sand.

If what you are trying to bend is the hobby shop stuff, you are probably fighting a loosing battle. Find a hardare store that carries aluminum refrigeration tubing. It comes in all sizes and is dead soft.

Les

Think the refrig. tube is strong enough for an exaust header?

How much pressure do you think there will be in the tube? It has two open ends and only carries the exhaust. It isn't like a boiler that holds a pressure.

They also make some tubing benders. They look like giant springs and come in all different sizes. They work really well. Good Luck, Dave

Laird, Wasn't worried about pressure, what about vibration and resonance? The only way to learn is to ask. I've seen people use copper tube, but don't like it much....

I have found that copper tubing works well even with 4 strokes-at least you can bend it easily and braze, solder if necessary. Aluminum tubing seems to vary in hardness, and some is difficult to impossible to bend. Aluminum tubing is also more susceptible to cracking due to vibration.

I've used various diameter metal tubing from the auto parts store ( short lengths of gas or brake line tubing) for headers for my four strokes. I would think the aluminum would be more prone to crack. Although the metal tubing is a little heavier, it does bend and silver solder very nicely. I usually take the tubing to the polishing wheel before I do any bending or cutting.

Anonemouse: I'm not sure. I have only used it for extensions from the stock header.

Les

Hey, what ever works. It's nice to have a resource of information at hand when you come up with a problem. I guess differen't applications would let you use one thing that might not work somewhere else very well......