Tube bending for racks/custom rack discussion

Please excuse me if I missed it, but is anyone using titanium to make racks? If so, what tubing? Given the limited availability and price of 5/16 .028 4130, I was toying with the idea of titanium for a light weight rack. Many thanks, Daniel

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Yes… I thought about that, but the idea is to carry just a duffel… small one, so I don’t think I need a stopper…

I don’t really know anyone who’s making out of titanium… but for sure there are people here…

that is planned to be my introduction to titanium welding… but haven’t looked much for tubes yet.,

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Tubus makes (or made?) Ti racks, but with the usual cost-cutting that any mass-producer needs to do, like tubes just welded to the side of another tube without a miter. I expect anyone here can do better than that.

3Al/2.5V is the “good” alloy, originally made as high-performance hydraulic tube for aircraft, so it’s meant to be good for bending, without so much of the thinning that tends to occur in the outer edge of the bend. I don’t know of anyone who sells it in the diameters you want for racks, but I haven’t looked. I see Online Metals only sells Grade 2, which is commercially-pure Ti, not alloy. Much weaker than 3/2.5. Dunno what Tubus uses but I would be surprised if they’re using alloy — probably CP. Which is so weak I wouldn’t bother, just use SS if you want corrosion-resistance or 4130 if you want light weight.

3/2.5, if you can get it, has a low stiffness-to-strength ratio, so if you use the same diameter as steel and build it to the same strength, it’ll be much more flexible. Usually not good in a rack that carries substantial weight. Extra wiggle in the cargo has bad effects on handling. Probably just fine for a light load like a typical handlebar bag though. But then, with those little Hbar bag racks, the potential for weight savings is small because you can make them so dang light in steel, so why bother with all that extra hassle of Ti? Just for bragging rights? Getting to the top of the hill milliseconds faster?

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How about 1/4" x .028" then? Even lighter, and Aircraft Spruce sells it (no doubt others too but it’s the first place I looked.)

Not suitable for heavy loads, but plenty for a typical Hbar bag, assuming proper design. That mostly means no curved struts in the load path down to the fork. Compression columns need to be straight.

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Great input bulgie, just the perspective I was after!

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