How to stiffen 1/2" aluminum tube?

[Myka]

Yes it makes sense. I was thinking along those lines too, but want to come up with a cleaner look than that.

I have some spared lengths so I'm going to try making a bigger radius bend. That might help enough.

If all else fails I'll hang it fron the ceiling, but I'm trying to avoid the industrial style look of that.

[hillegom]

If you are going to bend a new one, what about inserting a steel rod before you bend the aluminum. It will be harder to bend, but a lot stronger. And it will still look shiny

[Myka]

Originally Posted by hillegom

If you are going to bend a new one, what about inserting a steel rod before you bend the aluminum. It will be harder to bend, but a lot stronger. And it will still look shiny

I thought about trying to get a steel rod in there, but I overthought it and didn't think about inserting the rod before bending. How brilliant! I'll give this a try.

[Reef Pilot]

From my aircraft building experience: Two ways to do it.

1. Cut two pieces of same tube about 3 inches. Use a suitable size round file to shape the ends to fit over the bent tube to form a triangle corner support. Leave the ends slightly longer to form tabs where you drill and rivet to the main tube. And/or you can rivet the sides for extra strength and stability. Shape and file the edges to make it fit perfectly and look pretty. This will be the most professional finish.

2. Cut two small triangle aluminum gussets to fit on each side of the bent tube, and rivet (4 rivets per gusset). File to round the edges and it will look pretty good as well.

Also note that you should not mix aluminum and steel. Dissimilar metals cause corrosion and will eventually lose strength and loosen up.

[Myka]

Originally Posted by WarDog

Is that your foot? What the hell did you do to your toe?

That's just a bit of nail lacquer that I haven't managed to pick off yet.

Originally Posted by Reef Pilot

Also note that you should not mix aluminum and steel. Dissimilar metals cause corrosion and will eventually lose strength and loosen up.

I was a bit concerned about that, but I thought it took dampness to cause an issue. What if I wrap the steel in something first, like Tuck Tape or vapor barrier plastic?

Otherwise, option #1 sounds nice.

[Myka]

I didn't realize you could brush stainless or I would have used that right off the bat!

I'm going to try to work with what I already have (10 more feet of aluminum rod) and if that doesn't work then I'll just bite the bullet and hang it from the ceiling. Thanks for all your input Steve.

[mike31154]

That's definitely a wimpy looking piece of tube to be hanging 18 lbs or so near the end. Aluminum really isn't the best choice for something like this. Since you've already bent some up, have you tried hanging something close to 18 lbs to it to see what happens?

Not sure bending steel inside the alu will work all that well either. My guess (guess only) is that the aluminum outer will get crushed or deformed by the extra force required to bend the steel inside? That will ruin the look for sure.

My fixture hangs from the ceiling on spring wound retractable pulleys. Industrial, yes, but functional since it makes raising & lowering the fixture for maintenance a snap.

[Reef Pilot]

Or if you want something really strong (but still small diameter) you could use 4130 chrome moly steel tube (also a common item at metal shops). We use that to hang 400 lb engines on the front of a firewall. You won't bend it though, but a good tig welder can do a nice job for you.

[Myka]

Thanks for all your input guys. I think I done screwing around with it though, and I'm just going to hang it from the ceiling. I'll have to go play in the attic...

[sphelps]

You give up too easily. Take some some of that extra aluminum tube and cope in a knee brace on each support, rivet it in for a clean look. A knee brace deceases L which is cubed in the formula I posted previously, or in other words it's the most important variable.