Need Ti explaination...

Discussion in 'Cycling Equipment' started by Crystal, Jun 16, 2003.

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  1. Crystal

    Crystal Guest

    Greetings all... can someone please explain the difference between 3Al/2.5V titanium and
    6Al/4V titanium.

    Thanks Crystal
     
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  2. Kbh

    Kbh Guest

  3. Crystal

    Crystal Guest

    Seven has a great website, except that they will only send me their brochure "within the next
    few weeks"...

    Anyone else has an explination?

    Thanks Crystal
     
  4. G. Huang

    G. Huang Guest

    Crystal wrote:
    > Seven has a great website, except that they will only send me their brochure "within the next few
    > weeks"...
    >
    > Anyone else has an explination?
    >

    Both are Ti Alloys. 3Al/2.5V = 3% Aluminum and 2.5% Vanadium 6Al/4V = 6% Aluminum and 4% Vanadium

    6Al/4V has about 40% higher tensile strength and slightly higher Young's modulus.

    GH
     
  5. Skuke

    Skuke Guest

    Try http://www.habcycles.com/techstuf.html

    Strictly speaking, 3Al/2.5V has Ti with 3% Aluminum and 2.5% Vandium. You can guess what 6AL/4V is
    comprised of.

    skuke

    "Crystal" <[email protected]> wrote in message news:<[email protected]>...
    > Seven has a great website, except that they will only send me their brochure "within the next few
    > weeks"...
    >
    > Anyone else has an explination?
    >
    > Thanks Crystal
     
  6. Bfd

    Bfd Guest

    "Crystal" <[email protected]> wrote in message news:<[email protected]>...
    > Seven has a great website, except that they will only send me their brochure "within the next few
    > weeks"...
    >
    > Anyone else has an explination?
    >
    Here's some reading material: seven - http://www.sevencycles.com/technology/techtitantypes.html

    habanero - http://www.habcycles.com/techstuf.html

    Spectrum-cycles - http://www.spectrum-cycles.com/624.htm

    Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros, contact
    litespeed....
     
  7. Chalo

    Chalo Guest

    "Crystal" <[email protected]> wrote:

    > can someone please explain the difference between 3Al/2.5V titanium and 6Al/4V titanium.

    Compared to 3/2.5, 6/4 Ti has a higher tensile strength-- by about a third-- and lower
    ductility, much the same way that high carbon steel has higher strength and lower ductility that
    mild steel. 3/2.5 and
    6/4 have functionally identical density and stiffness.

    7/4 is easier to machine (cuts more cleanly) while 3/2.5 is easier to form (takes a tighter bend
    without cracking). So 3/2.5 is more suitable for drawing into tubes, while 6/4 is superior for
    dropouts, threaded bosses, cable stops and the like.

    There has been a great deal more hype about differentiating between these alloys than is warranted
    by their properties. There are processing implications for the manufacturer, but no practical
    distinctions for the end user.

    Chalo Colina
     
  8. > There are processing implications for the manufacturer, but no practical distinctions for the
    > end user.
    >

    Except Cost! Steve
     
  9. On Mon, 16 Jun 2003 15:30:35 +0000, bfd wrote:

    > Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros, contact
    > litespeed....

    Probably true. None of these sites (Sorry, Mark) is unbiased, in that they sell one or the other,
    and want to encourage you to buy theirs. Mark (Hickey, Habanero) does have one useful point, though.
    That is the gram/$ ratio. For a frame of comparable strength, the difference between 6/4 and
    3/2.5 will be small in terms of grams, but big in terms of dollars.

    Is it worth it to you? That is the decision to make. I have seen a frame that was claimed to be made
    of 6/4 alloy with seamless tubes. Most 6/4 tubes are not seamless, but rolled and welded. That
    clearly has problems in terms of weld imerfections. If indeed they have seamless tubes now, then
    that disadvantage is gone, if you are willing to pay for it.

    For me, the money did not buy happiness, and I went for one of Mark's frames. Nice, well-made, great
    ride. You choose.

    --

    David L. Johnson

    __o | The lottery is a tax on those who fail to understand _`\(,_ | mathematics. (_)/ (_) |
     
  10. bfd wrote:
    > "Crystal" <[email protected]> wrote in message news:<[email protected]>...
    >
    >>Seven has a great website, except that they will only send me their brochure "within the next few
    >>weeks"...
    >>
    >>Anyone else has an explination?
    >>
    >
    > Here's some reading material: seven - http://www.sevencycles.com/technology/techtitantypes.html
    >
    > habanero - http://www.habcycles.com/techstuf.html
    >
    > Spectrum-cycles - http://www.spectrum-cycles.com/624.htm
    >
    > Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros, contact
    > litespeed....

    Merlin and Litespeed Titanium are both titanium bicycle brands and are both owned by the American
    Bicycle Group (http://americanbicycle.eu.com/home.html). Both brands are produced in the same
    factory in Chattanooga, Tennessee.

    All frames that carry the Merlin name are made from 3Al/2.5V Ti, which the Merlin web pages say is
    the superior alloy for use in bicycle frames:

    http://www.merlinbike.com/english/tech/ti_history.html#grades

    However, several Litespeed models at the top end of their price scale are made from 6Al/4V ti, which
    the Litespeed web pages say is the superior alloy for bicycle frames:

    http://www.litespeed.com/english/technology/titanium.html
    http://www.litespeed.com/english/bikes/vortex.html

    Which half of the American Bicycle Group factory is fooling the other half?

    Mark McMaster [email protected]

    http://americanbicycle.eu.com/home.html
     
  11. Bfd

    Bfd Guest

    Mark McMaster <[email protected]> wrote in message news:<[email protected]>...
    > bfd wrote:
    > > "Crystal" <[email protected]> wrote in message
    > > news:<[email protected]>...
    > >
    > >>Seven has a great website, except that they will only send me their brochure "within the next
    > >>few weeks"...
    > >>
    > >>Anyone else has an explination?
    > >>
    > >
    > > Here's some reading material: seven - http://www.sevencycles.com/technology/techtitantypes.html
    > >
    > > habanero - http://www.habcycles.com/techstuf.html
    > >
    > > Spectrum-cycles - http://www.spectrum-cycles.com/624.htm
    > >
    > > Note - none of the above builders use 6/4 tubing, so there will be bias against. For pros,
    > > contact litespeed....
    >
    > Merlin and Litespeed Titanium are both titanium bicycle brands and are both owned by the American
    > Bicycle Group (http://americanbicycle.eu.com/home.html). Both brands are produced in the same
    > factory in Chattanooga, Tennessee.
    >
    > All frames that carry the Merlin name are made from 3Al/2.5V Ti, which the Merlin web pages say is
    > the superior alloy for use in bicycle frames:
    >
    > http://www.merlinbike.com/english/tech/ti_history.html#grades
    >
    > However, several Litespeed models at the top end of their price scale are made from 6Al/4V ti,
    > which the Litespeed web pages say is the superior alloy for bicycle frames:
    >
    > http://www.litespeed.com/english/technology/titanium.html
    > http://www.litespeed.com/english/bikes/vortex.html
    >
    > Which half of the American Bicycle Group factory is fooling the other half?
    >
    >
    I say neither. ABG is covering all bases so that if the consumer *believes* 3/2.5 is superior, they
    can buy either merlin or litespeed. Similarly, if the consumer *believes* 6/4 is superior, they got
    that covered. Either way, ABG has what people want and should make money on both....
     
  12. "David L. Johnson" <[email protected]> wrote in message
    news:<[email protected]>...

    > I have seen a frame that was claimed to be made of 6/4 alloy with seamless tubes. Most 6/4 tubes
    > are not seamless, but rolled and welded. That clearly has problems in terms of weld
    > imerfections. If indeed they have seamless tubes now, then that disadvantage is gone, if you are
    > willing to pay for it.

    6/4 Ti tubing is available in seamless, double-butted form from Reynolds, and features in Airborne's
    new flagship Torch frameset. As you say, though, it will make a big dent in your wallet.

    David E. Belcher

    Dept. of Chemistry, University of York
     
  13. John Carrier

    John Carrier Guest

    Refers to percentage of Aluminum and Vanadium in the Ti alloy. 6/4 has higher tensile strength but
    nearly identical modulus of elasticity (the same spec tube in 6/4 and 3/2.5 will have the same
    flexibility ... but the 3/2.5 will fail under a lesser ultimate load). Theoretically, you could
    manufacture a 6/4 frame that was lighter than 3/2.5. If advertised weights are reasonably accurate,
    this isn't true in practice. Theoretically, the
    6/4 frame could be stronger than a similar 3/2.5 frame. Doesn't appear to be meaningful in practice.

    7/4 tends to get brittle when cold-worked and is difficult (impossible) to draw into tubes. Most 6/4
    frames are fabricated from sheet and welded into (and sometimes cold-worked into multishape)
    tubes. Arguably, cold-working has a detrimental effect on fatigue strength, but that doesn't
    appear to be demonstrated in bicycle applications. Many frames use 6/4 for rear dropouts. Other
    fittings are usually CP (commercially pure) Ti.

    I assume that your question is to support a purchase decision. Either alloy can be made into an
    excellent frame. Neither variation of Ti, on the merits of the alloy alone, will result in a
    "better" product.

    R / John

    "Crystal" <[email protected]> wrote in message news:[email protected]...
    > Greetings all... can someone please explain the difference between
    3Al/2.5V
    > titanium and 6Al/4V titanium.
    >
    > Thanks Crystal
     
  14. On Fri, 20 Jun 2003 07:02:41 -0500, "John Carrier" <[email protected]> wrote:

    >Refers to percentage of Aluminum and Vanadium in the Ti alloy. 6/4 has higher tensile strength but
    >nearly identical modulus of elasticity (the same spec tube in 6/4 and 3/2.5 will have the same
    >flexibility ... but the 3/2.5 will fail under a lesser ultimate load). Theoretically, you could
    >manufacture a 6/4 frame that was lighter than 3/2.5.

    But then it'd be flexier, wouldn't it? Thinner walled tubes?

    Jasper
     
  15. Mark Hickey

    Mark Hickey Guest

    Jasper Janssen <[email protected]> wrote:

    >On Fri, 20 Jun 2003 07:02:41 -0500, "John Carrier" <[email protected]> wrote:
    >
    >>Refers to percentage of Aluminum and Vanadium in the Ti alloy. 6/4 has higher tensile strength but
    >>nearly identical modulus of elasticity (the same spec tube in 6/4 and 3/2.5 will have the same
    >>flexibility ... but the 3/2.5 will fail under a lesser ultimate load). Theoretically, you could
    >>manufacture a 6/4 frame that was lighter than 3/2.5.
    >
    >But then it'd be flexier, wouldn't it? Thinner walled tubes?

    The flex would be identical between the two alloys, if all other things are equal. The tradeoff is
    between ultimate strength and ductiliity (or more accurately, plastic deformation). 6/4 has higher
    ultimate stength than 3/2.5 (which makes it harder to tear the tubes in half - not normally a big
    problem for well-built frames of either alloy), but 6/4 has considerably less ductility. Plastic
    deformation is a measure of how far you can bend a piece of material before it's permanently
    deformed, and 3/2.5 has a distinct advantage there.

    If you push the envelope too far with either alloy by making the tubes thinner and thinner, you
    increase the flex. If the resultant flex is beyond the material's ability to "spring back", you have
    a misaligned frame.

    Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame
     
  16. Appkiller

    Appkiller Guest

    <snip)
    > 6/4 tends to get brittle when cold-worked and is difficult (impossible) to draw into tubes.
    <snip>

    Reynolds is making seamless 6/4 tubing. Butted as well, I believe.

    App
     
  17. John Carrier

    John Carrier Guest

    Theoretically, you could
    > >manufacture a 6/4 frame that was lighter than 3/2.5.
    >
    > But then it'd be flexier, wouldn't it? Thinner walled tubes?

    No, you could use your higher strength material to make a slightly larger diameter and slightly
    thinner-walled tube that would be overall lighter and just as stiff.

    R / John
     
  18. John Carrier

    John Carrier Guest

    I stand corrected. Meant to say "almost impossible." Reynolds, who frequently come up with
    innovative tube drawing solutions do make seamless
    6/4 tubes.

    R / John

    "Appkiller" <[email protected]> wrote in message
    news:[email protected]...
    > <snip)
    > > 6/4 tends to get brittle when cold-worked and is difficult (impossible)
    to
    > > draw into tubes.
    > <snip>
    >
    > Reynolds is making seamless 6/4 tubing. Butted as well, I believe.
    >
    > App
     
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