Advertise on Bikeforums.net



User Tag List

Results 1 to 8 of 8

Thread: fake cast stem

  1. #1
    Senior Member ftwelder's Avatar
    Join Date
    Apr 2010
    Location
    vermont
    My Bikes
    Many
    Posts
    3,093
    Mentioned
    7 Post(s)
    Tagged
    1 Thread(s)

    fake cast stem

    I have been trying to get my wife's bike to fit her better. I made this stem in three pieces and welded them together. The really funny part is I took her bike apart, removed the stem and didn't see the shims drop out so it still does not fit the bars properly.


    IMG_3554 by frankthewelder, on Flickr



    IMG_3553 by frankthewelder, on Flickr

  2. #2
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,475
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    nice. I've done some similar work with brass making woodworking tools.

  3. #3
    Senior Member ftwelder's Avatar
    Join Date
    Apr 2010
    Location
    vermont
    My Bikes
    Many
    Posts
    3,093
    Mentioned
    7 Post(s)
    Tagged
    1 Thread(s)
    Brass wood working tools?

  4. #4
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,475
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    wood planes -- you can tell I got some porosity

  5. #5
    tuz
    tuz is offline
    Senior Member
    Join Date
    Dec 2006
    Location
    Toronto/Montréal
    My Bikes
    Homemade mixte, track, commuter and road, Ryffranck road
    Posts
    1,137
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    That's pretty cool, looks like the real thing I like how the binder blends in. It was welded too? I wonder how you got the transitions so smooth everywhere.

    I'm tempted to try gas-welding aluminum one of these days...
    homebuilt commuter, mixte, road and track (+ Ryffranck road)
    bla bla blog

  6. #6
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,475
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I'd say it looks better than most cast stems. I'm guessing he got the transitions so smooth through good old-fashioned elbow grease.

  7. #7
    Senior Member ftwelder's Avatar
    Join Date
    Apr 2010
    Location
    vermont
    My Bikes
    Many
    Posts
    3,093
    Mentioned
    7 Post(s)
    Tagged
    1 Thread(s)
    the binder was machined into the clamp as one-piece. the extension is 1" X.120 wall, ovalized and the quill is a lathe made part. The whole thing took about 20 hours. Lots of filing.

    Aluminum transfers heat very quickly. Gas welding is very effective for sheet metal work and works a lot like steel brazing with a unique flux. Typically 1100 series filler is used as are special glasses. It is very difficult to get a thicker piece hot enough to use this method.


    that brass tool is neat. I don't think I have tried to gas-weld brass.

  8. #8
    tuz
    tuz is offline
    Senior Member
    Join Date
    Dec 2006
    Location
    Toronto/Montréal
    My Bikes
    Homemade mixte, track, commuter and road, Ryffranck road
    Posts
    1,137
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Cool. I'm not familiar with TIG but you don't often see smoothed weld, except on Canondales. Is there an extra step besides the filling and sanding?

    Regarding gas-welding Al. I'm wondering about it after seeing those older Aluminum French bikes (Barra and others) that were gas-welded (or brazed?).
    homebuilt commuter, mixte, road and track (+ Ryffranck road)
    bla bla blog

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •