bending curve

[lsw11]

hey,
i want to bend a nice curve in a piece of 2" 16 gauge exhaust tubing for my pipes. can this be done by just making a jig of the curve i want and bending it? will i need to heat it for it to work?
thanks

[simplySPiKE]

you will absolutely need to heat it to make a nice bend.
if you don't all you will get is a kink and/or a flat spot that bulges out on the sides.

before you bend the pipe, pack the pipe with sand and cap it off.
this will help keep the pipe looking uniform through the bend and keep it from collapsing.

if you havn't done it before, make sure you have extra pipe... because it takes a lot of practice to learn where the correct heat range is, and where to heat the pipe to keep the bend following one nice steady curve.

[simplySPiKE]

use a rosebud torch, and heat from the outside of the bend. the reason being that the outside metal is the metal you are trying to 'stretch' out, the heat allows you to do this. the inside of the bend does not change shape so much, and keeping it cooler than the outside will help keep the bend uniform and kink free.

[mle]

I think you would be better off buying the 90s or bends that you need and piecing them together. It is going to be pretty damn hard to make the bends without kinks ,rolls or dimples without a tubing bender. You can do it like simplySpike explained but you had better get a whole bunch of extra pipe.
Man is not perfect, machine is.

[lsw11]

Originally Posted by mle

I think you would be better off buying the 90s or bends that you need and piecing them together. It is going to be pretty damn hard to make the bends without kinks ,rolls or dimples without a tubing bender. You can do it like simplySpike explained but you had better get a whole bunch of extra pipe.
Man is not perfect, machine is.

i'm only bending the part that is going to have a large radius, i'm taking a couple feet, that normal bending machines cant make, only roll benders can. i will use u bends for the rest of it.

[Mothers Chopper]

Mandrel bent tubing is really the only way to bend it and it look right and smooth.
eBay Motors: 2" - 45 & 180 - 304 Stainless Mandrel Bend Pipe Tubing (item 380029422978 end time May-29-08 15:09:06 PDT)

[lsw11]

Originally Posted by Mothers Chopper

Mandrel bent tubing is really the only way to bend it and it look right and smooth.
eBay Motors: 2" - 45 & 180 - 304 Stainless Mandrel Bend Pipe Tubing (item 380029422978 end time May-29-08 15:09:06 PDT)

i'm not looking at making a tight radius bend, i want to make a large one, like a big arch. the link below is what i'm talking about, i'm just trying to make the curve.
Pipe Dreamz Custom Sportster Exhaust and More (714) 897-7473

i don't have torch setup at all. will using one of those small propane ones from lowes work or will it not beable to get it hot enough? i will be getting a 10' sections so i will have pretty good leverage on it to bend.

thanks

[Mothers Chopper]

I think I would cap one end, fill it with sand then cap the other end then try to put your radious on it. That should help with stopping it from distorting. If you can get one of the big propane torch like what is used to do roof work you may be able to get it done. They run off bbq grill tanks. Maybe try cutting the arch you want in a couple of pieces of lumber and spacing them a little apart to form a gully in between that them pipe can rest in. Strap it down on one end heat it and give it a go. Soak the wood in water. For small adjustments

[Barefoot Choppa]

Originally Posted by mle

Man is not perfect, machine is.

Man made machine....... Oh the irony..

[MechWerks]

Since it is big sweeping bends a wood form cut slight tighter than the final needed results should work (material springback). Getting things clamped down is the greater challenge. But if a long length of tube is available, the leverage will make things suprisingly easy. You will need excess material for selvage at either end of the bend...so don't try to take a 4' tube and expect to get two 2' bent usable lengths. Use a long tube and attempt to bend just the end. The heating will not be of much benefit on thin wall tube. Sand and capping can help...but also will not have too much benefit.

[gearsmithy]

just a note: if you pack it with sand be sure to bake the sand first to eliminate moisture, you wouldn't want that pipe expanding on you while you heat it.

[TRISH!]

we cut and bent the shit out of pipes and stock for struts on my bike and its true: heat the outside of the metal - HOT and bend slowly. reheat often. took me a few tries to see how it worked. but its easy for things to get out of wack or crooked - at least it was for me. i needed help. two sets of hands are better than one.

[tauruck]

Originally Posted by lsw11

i'm not looking at making a tight radius bend, i want to make a large one, like a big arch. the link below is what i'm talking about, i'm just trying to make the curve.
Pipe Dreamz Custom Sportster Exhaust and More (714) 897-7473

i don't have torch setup at all. will using one of those small propane ones from lowes work or will it not beable to get it hot enough? i will be getting a 10' sections so i will have pretty good leverage on it to bend.

thanks

Will you please let us know how it goes?. 2" exhaust tubing, large radius with torch by hand. I wish you luck, no Really.

[MechWerks]

FYI---the little propane torch is NOT going to be hot enough. You will be lucky to get one small spot heated to red hot (point where the tube will bend easy) but no chance at getting a length heated to take an even bend. If you consider the calorific heat coming out of an exhaust and the majority of that pipe not being red hot at any time...it sort of puts the little soldering/heating torch in perspective. You would need a torch with a massive rosebud end and a large supply of fuel or fuel/ox mix to heat enough tube.
If you make an arched form of some sort, secure one end of a decent length of tube to on end and slowly push the cold metal on to the form, a sweeping curve can be had. The trick is to go very slow and have a gradual start on the form. Make the form big enough to get all the bend you need in one bend. Expect the first couple feet of tube to be worthless (wrong shape..remember the gradual ramp into shape) and the last several feet used for leverage. Now, you can weld stuff onto the tube to add leverage if you don't want to waste too much tube, but there is always a price to doing thing.

[donald branscom]

You need it bent on a mandrel bender.

End of story.