is there a way to tell if my frame is Ti ???

[yeti575nut]

I bought a 04 racer x to be rebuilt to its former glory, im nearly done and this is a gift for my wife.

As I have worked on this bike I keep thinking the material the frame is constructed of seems different than aluminum.

Im building two bikes , one a yeti 575 and the titus and comparing the two the material just "feels" different so Im wondering if there is a way to tell if it actually is aluminum or titanium?

Is there a vin number or way to test to tell me, I purchased it thinking its aluminum but from the first time I looked at it I was thinking different.

Thanks

[craigstr]

Try a magnet. Should attract to ti as it is a steel.

[dustyduke22]

Try a magnet. Should attract to ti as it is a steel.

I think your thought process is off. Ti is not a steel and does not share its magnetic properties.

Look at the size of the welds. Al usually has large welds and Ti has very small beautiful welds! Ti is typically not painted also

Hope that helps and clears up any confusion

[craigstr]

Been wrong before, though it was a steel alloy.

[yeti575nut]

Been wrong before, though it was a steel alloy.

The bike is not painted, it looks raw but shiny, the welds are awesome, even better than my yeti and more compact in size , they look like small dimes stacked on one another.

[yeti575nut]

here is a weld picture...
and as you can see no paint and shiny finish which has never been polished..

[Smiff]

that'll be alu. ti welds tend to look much smaller and neater.

also craigstr.. wtf.. typical ti is 6AL4V meaning 90% Ti, 6% Alu, 4% Vanadium i think.
it's not magnetic.. would make things like replacement hips extremely dodgy in hospital scanners if it were.

edit: apparently "Ti" can have a very small amount of steel in. no idea how to tell Ti from Alu other than density, which is tricky on a bike frame..

[dustyduke22]

that'll be alu. ti welds tend to look much smaller and neater.

also craigstr.. wtf.. typical ti is 6AL4V meaning 90% Ti, 6% Alu, 4% Vanadium i think.
it's not magnetic.. would make things like replacement hips extremely dodgy in hospital scanners if it were.

edit: apparently "Ti" can have a very small amount of steel in. no idea how to tell Ti from Alu other than density, which is tricky on a bike frame..

The frame is for sure aluminum. No doubt about that. Ti has a destinct finish and build quality.

[craigstr]

Yeah, after some research, Ti does have trace amounts of iron which cause some magnetic attraction. Scanners can detect ti, my dad gets dinged everytime he flies due to two knee replacements.

[Smiff]

so the difference in feel will be down to tube thickness, or coatings (alloy is never bare, it will corrode, even if its just alu oxide, this is why the Raw Guapo is anodized) also alu has many different series, though they're pretty equivalent for bikes afaik. brant would probably know more about this..

[yeti575nut]

ok thanks guys , glad we could figure it out..

[Smiff]

it's very nicely welded alu, if that's any consolation, way less likely to fail than ti imho

ti looks like this



looks neat, but actually Ti is very hard to weld without weakening.

some alloy frames are smoothed after welding, which is how at a glance they can pass for carbon.

[yeti575nut]

thanks smiff, it is an awesome frame and the welds are awesome.
I have welded stuff since I was 14 and im not expert but have welded aluminum but Im not that good, I can make it nice but not this nice...

Thanks for the photo and I hope your correct and the aluminum holds up.

take care..

[Strafer.2]

A very simple test.
If a hacksaw can't cut it, then it's Ti, congratulations!
If it saws off, it's Al, and you need a new frame.

[qbert2000]

Yeah, after some research, Ti does have trace amounts of iron which cause some magnetic attraction. Scanners can detect ti, my dad gets dinged everytime he flies due to two knee replacements.

titanium is a chemical element. it has no iron in it unless someone alloys it with iron. the most common titanium in bikes is 3/2.5 titanium (3% Aluminum, 2.5% Vanadium, and 94.5% Titanium) was designed to be used as tubing. most 6/4 ti in the bike industry is used as dropouts or plates, not tubing. i think lynskey used to make aero downtubes for road bikes out of 6/4 ti sheets that they formed and welded up into shape.

airport scanners aren't looking for iron, i think they scan for densities beyond bone densities so they can pick up weapons, even guns using polymer frames. i don't think medical titanium uses iron alloyed ti

Medical Grade Titanium

Titanium 6AL4V and 6AL4V ELI, alloys made of 6% Aluminum and 4% Vanadium, are the most common types of titanium used in medicine. Because of its harmonizing factor with the human body, these titanium alloys are popularly used in medical procedures, as well as in body piercings. Also known as Gr. 5 and Gr. 23, these are some of the most familiar and readily available types of titanium in the US, with a number of distributors specializing in these specific grades.

don't know where you researched that ti has trace amounts of iron in it??

[Smiff]

god this is ridiculous haha, scanners i was talking about are MRI.

apparently 6Al4V (even medical grade) allows up to 0.25% iron:
http://www.londonimplantlab.com/docu...B_V3_print.pdf

(not only place i've seen the .25% figure..)

don't know if that's from impurities in ti ore or the production, or how much iron you need to make something magnetic!


back on topic, did Titus ever make a ti racer x?

[qbert2000]

god this is ridiculous haha, scanners i was talking about are MRI.

apparently 6Al4V (even medical grade) allows up to 0.25% iron:
http://www.londonimplantlab.com/docu...B_V3_print.pdf

(not only place i've seen the .25% figure..)

don't know if that's from impurities in ti ore or the production, or how much iron you need to make something magnetic!
back on topic, did Titus ever make a ti racer x?

damn, you ned a powerful magnet to pick up .25%. i know some cheaper offshore 304 stainless tubes are very slightly magnetic sometimes. when you weld them up yopu can see some of the impurities bubble to the surface.

but for sure the frame in question is aluminum as others have pointed out. big weld beads are a dead give away

i guess the aluminum frame would be as magnetic as the ti one as 7005 alloy can have up to .4% iron


Chemical composition

The alloy composition of 7005 is:
Aluminium 91.0% - 94.7%
Chromium 0.06% - 0.20%
Copper <=0.10 %
Iron <=0.40 %
Magnesium 1.0% - 1.80%
Manganese 0.20% - 0.70%
Silicon <=0.35%
Titanium 0.010% - 0.060%
Zinc 4.0% - 5.0%
Zirconium 0.080% - 0.20%
Other, total <= 0.15%

and 6061 up to .7%

Chemical composition
The alloy composition of 6061 is:
Silicon minimum 0.4%, maximum 0.8% by weight
Iron no minimum, maximum 0.7%
Copper minimum 0.15%, maximum 0.40%
Manganese no minimum, maximum 0.15%
Magnesium minimum 0.8%, maximum 1.2%
Chromium minimum 0.04%, maximum 0.35%
Zinc no minimum, maximum 0.25%
Titanium no minimum, maximum 0.15%
Other elements no more than 0.05% each, 0.15% total
Remainder Aluminium (95.85%–98.56%)

so i think actually neither would be magnetic. i've never had a magnet stick to an aluminum tube. wonder what percentage you'd need for a magnet to start to grab
[edit]

[Smiff]

i dunno but i have a shimano middle ring (slx 36t) that weakly magnetic. more than an alloy ring, and less than a steel. any ideas what it is?

[anvil_den]

Ti and Alu aren't attracted in the typical sense to a magnet, i.e. they aren't ferromagnetic. Paramagnetic, yes but that's a different thing altogether-- doubt most people ever apply an external current to their bike's tubings.

[Deerhill]

Ti is incredibly luxurious in the sun, finish in it is hard to mistake with paint once you get it outside.. unfinished welds look really cool too

[qbert2000]

i dunno but i have a shimano middle ring (slx 36t) that weakly magnetic. more than an alloy ring, and less than a steel. any ideas what it is?

at one point they were a steel/composite ring. i thought it was on the 32 tooth but i'm pretty sure they aren't just aluminum

[dustyduke22]

at one point they were a steel/composite ring. i thought it was on the 32 tooth but i'm pretty sure they aren't just aluminum

Ya, straight Aluminum would get shredded pretty fast.

[qbert2000]

Ya, straight Aluminum would get shredded pretty fast.

i dont know about that. race face, chromag, blackspire, renthal all use 7005 t6 aluminum for their rings with no real issues. renthal hard annodizes their rings as well, but 7005 t6 alloy is pretty hard and light

[dustyduke22]

i dont know about that. race face, chromag, blackspire, renthal all use 7005 t6 aluminum for their rings with no real issues. renthal hard annodizes their rings as well, but 7005 t6 alloy is pretty hard and light

Absolutely. All aluminum is not created equal.