Did I compromise my welds?

Discussion in 'General Bike Discussion' started by bmohan55, Jun 18, 2010.

  1. bmohan55

    bmohan55 Senior Member

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    I love my 1995 Bianchi Eros I've had since new.

    The other day the bolt that holds my seat on the seat post broke. In order to remove the seat post (couldn't match up the bolt) I had to use a propane torch to heat the Aluminum seat post and then dump water on it and let the different contraction rates seperate the two metals. I did this 5 or 6 times before the seat post broke free, the paint is burned and it looks simply awful.

    Now I'm worried that I have weakened the welds in the seat post area, think the old girl is still safe to hammer on or should she be given the retirement she has earned?

    Thanks
    Bob
     
  2. Industry_Hack

    Industry_Hack Total noob (& forum admin) Admin Staff Tavern Member

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    Hmm. How hot did it get, and how far along the tubing?
     

  3. bmohan55

    bmohan55 Senior Member

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    Not glowing red but hot enough to burnoff the paint. I used a white canister propane torch. Tried to keep it mosty on the seat post but went down about two inches of the tube. Had the shop guys here at the plant look at it and they said just by the heat/cool cycles I weakened the welds BUT they really don't know anything about the stresses I generate by bicycling so couldn't really say if I need to worry about it.

    Was wondering if anyone else had to do this and what the result was.

    Thanks
    Bob
     
  4. Industry_Hack

    Industry_Hack Total noob (& forum admin) Admin Staff Tavern Member

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    My guess would be that the quenching would possibly create hard and brittle welds. But that junction doesn't see the stresses of the BB or head tube. If you're a little guy, it should be ok. Off the top of my head, I don't recall ever seeing a road frame fail there.

    Unless it breaks, then I would like to retract the above quote, and replace it with "I told you so".
     
  5. bmohan55

    bmohan55 Senior Member

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    gotcha, thanks for your thoughts

    As much as I love my bike I "may" use this for an excuse to upgrade
     
  6. Industry_Hack

    Industry_Hack Total noob (& forum admin) Admin Staff Tavern Member

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    Excellent idea.