Bending Aluminum Pipe?

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Bending Aluminum Pipe?

Post by BillW » Sat Apr 02, 2005 12:22 am

I need to make a few parts for my boat. The electrical and steering hoses run to the upper station through the legs of the tower. The legs are full and I need more wire run up there. I want to fabricate another tube to run the new wire so it's nice and clean. I need to make a few 90 bends in some 1 inch and 2 inch aluminum pipe. I don't want real sharp bends. I bought one of the 12 ron hydraulic benders that Harbor freight sells.It didn't work too well. It bent the pipe but crushed the top as the two rollers on top don't conform to the shape of the pipe.

I won't need to make many parts so I don't want to spend a grand on a high dollar bender.

The next project will be a new bow rail out of 1 inch stanless steel. This will require a 180 degree bend with about 15 inches in the gap. This is the bow pulpit.

I'd appreciate any advice you guys could provide in the right tool for the job and techniques. The manual indicated I shoudl fill the pipe with sand to keep it from collapsing. Sounds reasonable but I didn't read the manual until after I tested it on some scrap material.




Re: Bending Aluminum Pipe?

Post by Greg_S » Sat Apr 02, 2005 1:03 am

Hi Bill,
I realize you are probably asking how you can do this yourself, but if you end up just wanting to get the job done then I have a suggestion.
I use a Greenlee 555 electric powered conduit bender in my shop. Just load up the pipe, press the button and stand back and smile as it bends that pipe to any angle you want up to 180 degrees. Any electrical contractor will own one, they have been made for years and years and are very common. It will do the job to your satisfaction.
Sand is good also. When I feel I must use sand, I just use those rubber test plugs that plumbers use to cap off the pipe (available at any hardware store) to hold in the sand. You might think that in bending it would just push those right out of the ends but that has not been my experience. Wet the sand a bit if any trouble.

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Re: Bending Aluminum Pipe?

Post by Orrin » Sat Apr 02, 2005 9:23 am

Brass musical instrument makers fill the tubes with water and freeze them, then bend. At least one manufacturer adds dishwashing detergent to the water. It keeps the ice from getting hard.

It's just a thought.

So many projects, so little time.

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Re: Bending Aluminum Pipe?

Post by Ries » Sat Apr 02, 2005 7:35 pm

Is this like "brakeless bending"? everybody wants to do the hard jobs without the right tools. Can I lift my 40 ft container without a crane? Fly to Japan without an airplane?
Some stuff is expensive, because it is actually hard to do.

I work a lot with a company that makes boat railings- thats all they do. Usually for 16 ga, 1" diameter stainless tube. They use a di-acro style bender to do most of their bends. Works great, no kinking, and they dont usually fill with sand. But a new di-acro is about 2500$, plus dies. and the dies have to fit very well, or else the bends dont turn out right.
I would suggest that this is a job to send out, to someone who has already spent the big bucks on the right tooling. If you can weld the stainless, there is no reason you need a huge piece- you can just have somebody bend you the 180, and UPS it to you, with a foot or so of pipe on each end, then weld it to the long pieces. Where are you located, and are there any boat railing fabricators nearby?


Re: Bending Aluminum Pipe?

Post by sailingamerican » Sun Apr 17, 2005 5:40 pm

Go to a mufler shop. They will have a tube bender and will be gald to bend your tubing for a small fee. Now for the real question. Why aluminum? If you are on salt water forget it. It will pit and go bad in a very short time. Have the rails made up of stainless or buy them. I am an architect and contractor. I have replaced a lot of aluminum hand rails on buildings and homes that are near the ocean. Tiwan is the scrap metal junk yard of the world. Many of the boat parts they make are crap. If you are going to all that work, time and effort why not make them right.


Re: Bending Aluminum Pipe?

Post by squidley » Tue Jun 14, 2005 4:34 pm

aluminum is used everywhere in the world on boats for several applacations even boat railing, if you don't paint it it will be fine.

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Re: Bending Aluminum Pipe?

Post by D_R » Tue Jun 14, 2005 8:07 pm

"Go to a mufler shop. They will have a tube bender and will be gald to bend your tubing for a small fee. "

Muffler shops have benders meant for relatively thin wall exhaust pipe. The dies they use are different than a conventional tube bending die.

There's a chance if the size pipe is near a standard set of their dies it might work, but I wouldn't count on it.


Re: Bending Aluminum Pipe?

Post by LJW » Tue Aug 30, 2005 12:28 pm

I built a fly bridge top
for my boat , a 40' Striker, out of regular alum pipe. Made a full
size dwg on an old piece of carpet hauled it down to the muffler shop. 20 mins & 20
bucks later, I had all the bends I needed with very little tweaking. That was 25 years ago. No corrosion no pitting and no sunshine or rain. I left it bare.
Painting alum is not all that straight forward. How do I know? My Striker is all aluminum.
aloha , Les

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Post by sandman2234 » Fri Jan 26, 2007 8:01 pm

If you have a mill and a rotary table and some ball endmills, consider wooden dies and a mechanical arm to bend it with.
I agree that most muffler shops will make a mess out of your expensive aluminum. I worked for a shop and a boat T-top/towers shop was using the other end of the building. I have been known to wander over there when things are slow.
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Bending aluminum tubing

Post by jeep » Sun Jul 01, 2007 12:22 pm

Not sure if you have made your pipe bends yet, however I have heard that soft tubing can be filled (packed) with sand or salt insuring no air pockets. Salt is supposidly easier to get beck out because it can be flushed out with water once your done. To do it, you plug one end with a wood plug, then fill with fine salt or sand. Plug the open end & then use your bender.

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Re: Bending aluminum tubing

Post by SteveM » Tue Aug 07, 2007 11:50 am

jeep wrote:Not sure if you have made your pipe bends yet, however I have heard that soft tubing can be filled (packed) with sand or salt insuring no air pockets.
I did exactly that when I needed to bend stainless steel tubing for upper and lower stress bars on my Rabbit GTI (this is going back a number of years).

I filled the tubes with sand, packed it down and taped the ends shut with duct tape. Then I jacked up a wheel, put one ond of the bar on the ground under it and pulled up on the other end, using the tire as a form. It bent well with no kinking.


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Re: Bending Aluminum Pipe?

Post by Bentworker » Sun Nov 25, 2012 12:59 pm

Be aware of what alloy of Aluminum you are buying. A lot of aluminum pipe is used by electric utilities for bus in substations. When I used to work for another utility we had a guy on another crew nearly loose his hand while bending a section of bus. He was using a Greenlee 884 on a tabletop trying to bend a section of 3 or 4 inch aluminum pipe. He got it to about 30 degrees when the pipe broke and the shrapnel and pipe sections nearly amputated his hand. Long story short he no longer has proper use of his hand after many surgeries.

The company was buying two different types of aluminum pipe. One was more rigid and one was malleable. Wrong pipe + bender = disaster.

I was able to make some pretty nice bends with a 884, and also used a 555 with good luck. Keeping the dies and rollers lubed seemed to help. Any decent electrical contractor should have one of this those machines.

As for bending stainless tube... It is a pain. That is something best done on a high dollar mandrel bender. I've had the local muffler guy bend up some 1.5 and 2" .060 for me before, the bent tube will shrink and look crummy. You may be better off purchasing bent sections and tig welding them together. Nice mandrel bent stainless can be found online.
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