Advertise on Bikeforums.net



User Tag List

Results 1 to 20 of 20
  1. #1
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    1 inch conduit bender to bend frok stays??

    Anybody has used this relatively non expensive conduit benders to bend fork stays?? Some are big enough so the curve radius gets pretty long/big... anybody? experiences???

    Just asking because is faster just get one of those than cut and fabricate a bender at home with wood and stuff.

    Thanks.

  2. #2
    Senior Member mudboy's Avatar
    Join Date
    Sep 2008
    Location
    Collegeville, PA
    My Bikes
    Ruckelshaus Randonneur, Specialized Allez (early 90's, steel), Ruckelshaus Path Bomber currently being built
    Posts
    1,353
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I've thought about this myself. I think the difficulty would be in repeatability of bends, i.e. getting two blades bent exactly the same.
    --~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--
    Ruckelshaus Randonneur Ruckelshaus Path Bomber
    Flickr Photostream
    FrameBuilderSource.com Framebuilder Database

  3. #3
    Senior Member Cassave's Avatar
    Join Date
    Jul 2005
    Location
    Woodland Hills, Calif.
    Posts
    1,512
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I used one many years ago, in fact that's what drove me to make my own bender.

    The stop on most conduit benders is about 2 inches from the edge of the radial segment the tube gets bent over, that leaves a 2 inch straight section at the bottom of the blade.
    To start the bend closer to the end of the blade you'll need to add a stop closer to the segment, not too tough to do.

  4. #4
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,659
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I think you'll end up flattening the blades. Making one out of wood or even steel is not that big of a deal.

  5. #5
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Interesting, well the device has marks the thing is to find one big enough because i think the curve in the 1 inch one is too small. Maybe u guys are right, might be better just to make one, Hmm... have some piece of laminated floor moving around...

  6. #6
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I think i found the perfect piece of wood and is even already cut... I bought long time ago this corner of an ikea desk, I took it off and put it in the garage, today while cleaning the garage i found it and it could work great i believe. What I was thinking is to cut an old tubular rim and put it to the sides around the edge to just keep the blades center. Can't remember what I paid but wasn't that expensive.

    Anybody likes the idea?



  7. #7
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,659
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    it might be a little too narrow, and the radius isn't right. I think that would be perfect for bending top tubes

  8. #8
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Hmm... do you have plans with a cut out of the radius that should be?

  9. #9
    Senior Member PaPa's Avatar
    Join Date
    May 2003
    Location
    Idaho
    Posts
    494
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by ultraman6970 View Post
    Anybody has used this relatively non expensive conduit benders to bend fork stays??
    Yup.

    Been using one made by Ideal #74-031 (labeled 1/2" EMT) for 12 years now. I clamp the bender handle in the bench vice (not the fork), measure and mark each blade and alternate bending - a little on one blade, then repeat on the other. Successfully tweaked about 30 road forks so far and have yet to wrinkle or kink one. However, I would strongly discourage bending MTB forks with this method.

  10. #10
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,659
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    are you just tweaking, or starting from new blades?

  11. #11
    Decrepit Member Scooper's Avatar
    Join Date
    Aug 2005
    Location
    San Francisco California
    My Bikes
    Waterford 953 RS-22
    Posts
    8,817
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Here's Tim Paterek's fork blade bender from an early version of the Paterek Manual, which can be downloaded free from http://www.timpaterek.com/paterek.pdf.

    - Stan

  12. #12
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by unterhausen View Post
    are you just tweaking, or starting from new blades?
    New ones, my master builder retired and i got stuck with tubes and lugs so why not give it a try. My other option to avod the issue bending the blades is getting a 7 degree fork crown and just go straight.

  13. #13
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thanks!

    Quote Originally Posted by Scooper View Post
    Here's Tim Paterek's fork blade bender from an early version of the Paterek Manual, which can be downloaded free from http://www.timpaterek.com/paterek.pdf.


  14. #14
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    HI, measured the radius in the table piece i had and is 43.83cm that is around 17.5 inches... is that a problem?

  15. #15
    coprolite fietsbob's Avatar
    Join Date
    Jun 2010
    Location
    NW,Oregon Coast
    My Bikes
    7
    Posts
    1,722
    Mentioned
    35 Post(s)
    Tagged
    0 Thread(s)
    consider making 2 duplicate curved forms, stack cutting on a bandsaw, perhaps?

    then build the fork with straight blades, bend the completed fork .
    that should result in consistent symmetrical rakes.

  16. #16
    Framebuilder
    Join Date
    Dec 2007
    Posts
    480
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by ultraman6970 View Post
    HI, measured the radius in the table piece i had and is 43.83cm that is around 17.5 inches... is that a problem?
    Depends on the curve you want. 17.5" would make a big ugly curve, imo. Classic rando forks are usually around 6-7". My personal form has an increasing radius that starts at 6.5" and ends at 8.5"...it's all in your sense of aesthetics.

  17. #17
    Framebuilder
    Join Date
    Dec 2007
    Posts
    480
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by fietsbob View Post
    consider making 2 duplicate curved forms, stack cutting on a bandsaw, perhaps?

    then build the fork with straight blades, bend the completed fork .

    that should result in consistent symmetrical rakes.
    But then you end up with a straight section right at the dropouts. Bending the blades before any brazing gives you a much greater control over the appearance of the finished fork.

  18. #18
    Senior Member
    Join Date
    Dec 2005
    Posts
    7,819
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Ok, you guys were right, it is too much radius. I made a cardboard fork using my radius and looks aweful, have another idea tho, hope this one works.

  19. #19
    Senior Member
    Join Date
    Jun 2006
    Posts
    8,354
    Mentioned
    12 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Live Wire View Post
    But then you end up with a straight section right at the dropouts. Bending the blades before any brazing gives you a much greater control over the appearance of the finished fork.
    This is not always true. Masi Carlsbad and Mario Confente both brazed them up straight then raked them. if you look at the bend it appears parabolic, and the fixture was too.

  20. #20
    Framebuilder
    Join Date
    Dec 2007
    Posts
    480
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by repechage View Post
    This is not always true. Masi Carlsbad and Mario Confente both brazed them up straight then raked them. if you look at the bend it appears parabolic, and the fixture was too.
    Just googled a bunch of Confente and Old Masi pics, and while I don't know where you see a parabola, all the pics illusrate my point. All of the blades had a small straight section right behind the drop which is what happens when you bend the blades with the drop brazed in. Not a big deal either way, but like I said before, cutting the blades after bending gives you more control over the final appearance.

Posting Permissions

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