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boludo

Since i spend, like most of you freaks, hours a day perusing MTB stuff and this site, I just came across another one of those WTF moments.

Look at these two bikes and tell me, besides name, graphics and shock, whats the diff? Another example of "dont buy the name, buy the components."

http://www.ibexbikes.com/Bikes/ATLAS...M-Details.html

http://www.azonicusa.com/catalog/pro...e32c55a7323cea

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CeeDubb

Two totally different frames...

The Azonic has way more stickers.

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FatWhat?

One goes to the left, the other to the right. Are they like stock cars in that it's damn near impossible to turn them the other way?

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Soc Eye

Different aluminum. This was the difference between the Santa Cruz frames and the Supergo Weighless knockoffs of yesteryear. Now, what difference the type of aluminum makes I have no idea.

boludo

The numbers are standard designations for aluminum alloys. Pure aluminum isn't the best material for many uses, most applications are for alloys. The 6000 series alloys uses silicon and magnesium to get their strenght, the 7000 series uses zinc. There are other series, with different additions. In addition to the additional elements, much of the material strength is controlled by post forming treatments. A combination of cold working, and heat treatments, they let you make a balance between a number of properties, such as strength, brittleness, and even corrosion resistance. These are designated by a T number following the alloy designation. (T4,T6,T10, etc)There are two basic ways to build a bike frame from aluminum, you can bond (aka glue) it together, or you can weld it. Both can produce good strong frames, if correct techniques, and good choices of material are made. Bonding allows a much greater choice of alloys, as most aluminum alloys don't want to be welded. (inculuding some of the strongest ones). It also doesn't thermally stress the tubes, so no post fabrication heat treatment is required. Bonding requires some sort of "lug" or other joint reenforcement, and very scrupulous technique.
Welding cuts down on your choice of alloy, and in the bike world, the two most commonly used are 6061, and 7005. When you weld a frame, you will have to heat treat the result, without it, the joints are quite fragile.
Both alloys get equivalent heat treatments, the exact amounts differ. As a result, you can't mix the two in the same welded frame. (you could bond them however). 7000 series has an advantage that it is hard to anneal, and thus degrades less with welding. The result: If you start from heat treated and aged tube, you can often avoid having to solution heat treat the whole frame after welding. The tube is delivered with heat treatment, and half of the artifical aging already done, and if treated with care, will only require some additional artifical aging after the frame is finish joined. 6061, with its greater sensitivity (its a lot easier to anneal, it only needs 2.5 hours of heating to anneal, 7005 needs 11), will require that the whole frame be heat treated after welding.
Avoiding the heat treat phase is a good thing, as it requires much higher temperatures. Artifical age can be done in a pizza oven, heat treating requres purpose built ovens.

Heat treating directions are based on information provided by Easton (which sells both 6061 and 7005 tube).

Normal processing for 7005 tube
(assumes that you don't need to put a significant bend in anything) (all temps quoted are in Farenheight, and are to be maintained within +- 10 degrees F)
1. Weld. Either GTA or GMA (aka TIG or MIG)
2. Align. Do this as soon as possible after welding, within 6 hours, or the frames lifespan can be compromised.
3. Artificial age. For whole frames, from factory heat treated tubes, 6 hours at 200 F, then 4 hours at 320 F.
If you need to bend or crimp a tube, you have to anneal it first.
Anneal 7005.
2 hours at 700 F, then turn down the temprature 50 F per hour until 450 F. Hold two hours at 450, then air cool.
Once annealed, you can form it. After forming, you need to soulution heat treat, delay and do the first stage of artifical age.
Heat treat 7005
Soak at 850 F for 30 min, then quench, with water, water/glycol, water spray, or forced air. When water quenching, water temp should never exceed 100F.
When cooling with air or water spray, quench rate must be faster than 4F per second. Higher quench speeds produce greater strenght, but
higher distortion.
If you heat treat a tube, you need to do half of the artifical ageing to it before welding. After a 72 hour room temperature delay, the same time and temp profile as above are used. (6 hr 200f, 4 hr 320F) Tubes shipped from the factory are in this state. You can then process as normal. (weld, align, age)
Whole frame heat treat and age, 7005
You can heat treat single tubes or the entire frame. If you heat treat an entire finish welded frame, you align it after the heat treat quench. You
then have to delay at room temprature for a minimum of 72 hours, and do a more extensive artifical age. 8 hours at 225F, then 16 hours at
300F. (as the normal process divides the aging)

6061, Normal processing.
1. Weld -- again TIG or MIG are the choices.
2. Solution heat treat. 30 minutes at 980 F. Quench in water or water/glycol (no option for mist or air), keeping quench liquid at 100F or lower.
3. Align. Again, you want to do this as soon as the material is quenched, max of 8 hours. The more you wait, the harder aligning becomes, and the greater the residual stress that gets locked in. This can make the material less resistant to fatigue failure.
4. Delay. At least 72 hours at room temprature.
5. Artifical age. 8 hours at 350F.
If you need to make significant bends or crimps in 6061 you have to anneal. This is a much faster process than with 7000 series. Only 2 hours at 675F, then reduce temperature to 650F, and soak 30 minutes. Follow by air cool, then form as soon as possible after that. No need to heat treat before welding, as the whole frame will get it afterwards.

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stinkyrider

damn.

BrewMaster

The only difference I see are the shocks (negligible since any shock can be used) and the little bolt/brace across the chain stay of the Ibex near the pivot.

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OldDogDan

That's interesting to see the same frame with different names. But actually they both have the same standard price. One's on sale now.

DownHillPhil

There are some subtle differences in the welds and material shapes used - note the triangle portion of the swingarm towards the back. Also right at the headtube and top tube intersection the lower part isn't exactly the same.

all things considered though they're basically the same bike


Edit: maybe i'm on crack - looks like a trick of photography perhaps.

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Division 26 Clothing

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tbowren

Wow I had no idea how much work went into making an aluminum frame.

I have always had a lot of respect for frame builders, that does not look like an easy job.

My Leviathan says "6061 T6 Aluminum". Now I have a better idea of what that means.

DeeZee

does not manufacture any of their parts. They are picked out of a catalog.

True story........

IMO best bang for your buck product in the market

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OldDogDan

Good tutorial! Most people have little idea about the science behind the art.

But bonded aluminum frames? Is there actually any current bike builder doing that (other than some Unabiker making one frame a year in his cabin?)? Not saying it wouldn't make a good or at least very "cool" bike. But most people trust a weld more (although, yes, bonded carbon fiber is somewhat popular).

CeeDubb

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slowSSer

current? zero idea. Trek's aluminum roadies used to be bonded. but that was back in the late 80's/early 90s.

Boludo: thanks for the rundown. amazing amount of knowledge you've got there.

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boludo

Thanks for all the kudos, but I just typed in 6061 & 7005 into google and that popped up. Then did a magical ctrl+a, ctrl+c, then ctrl+v, and then sat back and looked like a genious.

i learnt as much as all you.

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CeeDubb

Damn Windows users...

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BrewMaster

eh, having been an Ibex owner, I was less than impressed. bang for the buck is true to some degree, but my Ibex left a lot to be desired. their specs keep getting better, but never enough to win me over again.

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boludo

No doubt. Ibex is the marijuana of biking. Its an intro to the real world of bikes.

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drew12

Like the title says..crack Smokin' ....

sladnas

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