Tubing Bender

[Mikelly]

ONLY using the Northern unit I have... The unit Jody is using from Harbour Freight seems to have different dies for the bender and seems to work well... If you're going this route, get what Jody has... mine will end up as a mini-press and that's about all I can see using it for...

Mike

[JMortensen]

OK, so Jody, is this the right one??? Seems to be the largest that HF carries.

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=35336

[jbc3]

That's the one I bought.

[JMortensen]

Thanks Jody!

[Owen]

Ooh, it's on sale too! If only it was a local store price...

 

So how did the exhaust tubing work out?

Owen

[Trevor]

Any exhaust-gage tubing results yet? My results (with 17-gage & 18-gage thin wall standard ex pipe tube and the HF bender dies) were disappointing, I'll get some 2" pipe couplings and try it soon if no one else has....

[Owen]

I PMed jbc3 about this a while ago and was told that he couldn't find adequate sized couplings to use. But recently, on some jeep site, I saw that people were cutting the couplings in half and putting them in between the pipe/tube and the dies. I don't think anyone has tried exhaust tubing though.I also saw that some were using the bender horizontally (laid flat).

 

I'd like to bend up to 3" tubing, can that be done with the cheaper HF bender? Or will I have to get the $200 one?

Owen

[AK-Z]

I say build a bender. Buy some dyes and build a frame with a c-clamp for adjustment in depth and gradually bend that pipe. Then cut sections out for what you need and weld straight pipe on to that.

 

Another thing is that, if you are using a bender that wants make the pipe wrinkle in on itself, use a canvas bag, fill it with sand and put it inside the pipe. It will help with the wrinkling.

[alexideways]

Hey AK-Z, this is a good one, I'v been thinking about that for a while but had fear that the bag bould get stuck in the pipe, this ever happened to you?

Anyways, good to see that my idea is'nt worthless as some have told me.

[Tim240z]

I have also heard that filling the section of pipe with sand then tack welding the ends closed then bending will eliminate the kinking and wrinkling. Then just grind off the welds and let the sand run out.....

[Some-Guy]

I bought the same bender as that orange one posted there for 114$ Canadian From princess auto and its actualy pretty damn good just wait for the sale !! or ya check harbor freight cheaper to buy one of those cheap ones than build one plus you get all the dies!

[AK-Z]

Hey AK-Z' date=' this is a good one, I'v been thinking about that for a while but had fear that the bag bould get stuck in the pipe, this ever happened to you?

Anyways, good to see that my idea is'nt worthless as some have told me.[/quote']

 

It does get stuck some times. Just take a knife to it and have the sand run out.

[Z-TARD]

I've used sand in tubing before to make hot bends using a torch. A good way to seal the ends is to use tapered wooden plugs, the force of pounding them in also packs the sand in tighter for even better wrinkle resistance. Hot bending can make some really tight radius bends, but I'm not sure if it's legal to bend roll cage tube with this method as it tends to change the mechanical properties of the metal after heating. The trick to hot bending is to do it a little section at a time.

 

Mark of the bend area into 1" sections, enough to cover the length of the bend area.

 

Divide the degree of the bend by how many 1" sections you have marked off. If you want to make a 90 degree bend over a length of 6 inches, each section will be bent 15 degrees, etc.

 

Clamp the tube or pipe firmly in a vice that is attached to a heavy table. Have a 5 or 6 foot section of pipe available that will fit over the outside of the tube you are bending. Heat up the first secton (the one closest to the vice jaws) until it glows a dull red color. It helps to dim the lights a little when doing this, as dull red in a brightly lit room is significantly hotter than dull red in a dimly lit room. Once you have the entire i" section glowing around the circumfrence of the tube, slip the extra length of pipe over the other end and slide it down until it is only a few inches away from the heated area. You can do this by yourself with enough practice, but it really helps to have a friend pushing on the pipe while you heat with the torch, or visa versa. Slowly bend each section the required 15 degrees, having a wire template to compare against really helps to get the right angle. Using a bubble level on the legnth of pipe will also help you to maintain your horizontal angle, it's pretty common to end up with bends that angle down towards the floor if you're not paying attention. Once a section has reached 15 degrees, move the torch to the next section and repeat the process until you have the desired bend.

 

It takes some time to get the hang of it, there are a lot of tricks to making a smooth looking bend. Cutting the sections down to 1/2" will make it look a lot smoother, but a wire template is pretty much mandatory to make sure you don't over or under bend when the sections are that short. Concentrating heat on the inside and outside of the bend radius also helps prevent kinking on the sides. And again, I'm not sure about the legality of using this on roll cage tube, so bend at your own risk. Maybe someone more familiar with the rules and regulations can chime in on this.

 

Mike

[AK-Z]

Huh. I have to try that sometime. Wooden plugs you say, good idea. Might have to use a slide hammer to get it out, I would imagine.

[Z-TARD]

Normally they come out without too much hassle. Just remember to leave enough sticking out to grab onto with some channel lock pliers. If all else fails, set the torch to an oxidizing flame and burn that sucker out.

[JMortensen]

Jody, I hope you're out there and might be able to help me out. I'm finally getting around to this a year and a half later, and I just got my HF bender. It appears to be exactly the same one that you have. Unfortunately, I'm not having the same results.

 

I resized your old pics so that people could see what we're talking about.

 

I am using 1 3/4" x .120 wall DOM tubing. I thought maybe I would need to step up to the next size die, the 1 1/2" size. It measures 1 7/8 inside the arch of the die. So I gave that a shot and it was obviously a mistake. The tubing swelled out to fit the width of the die and kinked in the middle.

 

 

Then I figured what the hell and tried bending some of the 1 3/4" pipe in the smaller die. This actually came out a LOT better, but still isn't good enough for me (or a tech inspector). Here's how it came out with the smaller die.

 

 

If you're into drag racing I'm wondering if you might be using the .134 wall tubing and if that makes the difference with respect to the kinking. I know the bender says for thin walled tubing you might have to fill the tubes with sand. I'm not really excited about the prospect of having to fill all of these tubes with sand, I think I'd rather sell this thing and get a different bender. I am using a sleeve and that does seem to be keeping the ends from kinking, but I just can't seem to get the middle to bend without kinking. Any ideas for me? Am I doing something else obviously wrong?

[jeromio]

That kinking is exactly what I produced with the HF bender. I also tried the sand+heat. I filled with sand, welded large washers on the ends and then nuts and then bolts - figured I could tighten the bolts to compress the sand, remove air pockets. Anyway, I put it in the bender and then heated the whole bend area while pumping on the cyl.

 

The result was a very nice 90* bend. Almost perfect actually. However, it took about an hour. And that does not include the prep (filling and capping the tubing). In the process, I popped the welds on the bender and had to basically rebuild the frame.

 

When I stepped back and admired my one bend and then calculated how many bends I would need - well, I decided this was not going to be a good use of my time.

 

So, I'm saving my pennies for a proper bender....

[Owen]

A friend and I split the cost on one of these as well. We did some bends for his cage with what Jon used and made some nice 45s, but 90s are a huge pain. We just heated the tube and pumped the cylinder real slow.

 

I have had zero luck with thin wall tubing, steel and aluminum. The last time I tried it, I wrapped a dozen or so hose clamps in the bend area to try to prevent the tube squishing outwards, no good...damnit.

 

I wonder if it has to do with the shape of the die? The proper benders seem to have more of an arc to them.

[JMortensen]

So Owen you were able to get a decent 90 degree bend by heating the tube first, no sand? I have a MAPP gas torch, so that wouldn't be a problem.

 

I'm thinking that I'm not going to be building a whole bunch of race cars so if I can make this work I'd like to. I was thinking again about the sand, and I'm thinking there are really only 6 bars that I want to bend. The halo, the A pillar bars, the shoulder bar behind the seat, and the door bars. All the rest that I was planning on will be straight. Thinking about giving it another shot with sand or heat, or both...

[V8_DatZun]

from the pic.. those black pieces that the tube gets pushed up against.. if you move them out a little farther from the actual bend by a few holes wouldnt it allow the tube to be bent a little easier? to me it looks like after it tries to go up to get the actual bend those black pieces are smashing the tube.. in my mind it would be like trying to push a flexible rod through a TINY opening... it would be pretty hard and crease it... but if the opening is bigger it would just bend it.. then allow it to pass through easily.. not exactly the same concept.. but then again it is... i'd try that... although yours may not be setup like the ones in the pic are.