Advertise on Bikeforums.net



User Tag List

Results 1 to 8 of 8
  1. #1
    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
    1,354
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Homebuilt jigs & helpers

    I needed some dummy axles. While perusing McMaster-Carr one evening, I realized they had everything I need to make a couple of dummy axles, and then I built a rear brake bridge jig that also works for barrel-type rear rack braze-ons. Rather than create a long, drawn-out post here, I uploaded the photos to my flickr account and made complete annotations.

    Homebuilt frame jigs

    I hope this helps someone. If you have any questions, post them to Flickr so I can answer there. The two dummy axles and the brake bridge jig took less than two hours.

    I plan on building an Arctos-style jig at some point in the future out of 8020, which I will also fully document.

    Pete
    --~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--
    Ruckelshaus Randonneur Ruckelshaus Path Bomber
    Flickr Photostream
    FrameBuilderSource.com Framebuilder Database

  2. #2
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,744
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    it seems to me that your brake bridge jig isn't going to hold the brake parallel to the stays.

  3. #3
    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
    1,354
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by unterhausen View Post
    it seems to me that your brake bridge jig isn't going to hold the brake parallel to the stays.
    Yeah, I have yet to try it in practice; I angled the M6 screw downwards (upwards? Away from the base of the jig) a bit in the hopes that would properly compensate. I'm sure it will get tweaked once I have the stays in place. Worst case scenario is that I use a small U bolt to hold the bottom part of the fixture to the dummy axle.
    --~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--~--
    Ruckelshaus Randonneur Ruckelshaus Path Bomber
    Flickr Photostream
    FrameBuilderSource.com Framebuilder Database

  4. #4
    Old fart JohnDThompson's Avatar
    Join Date
    Nov 2004
    Location
    Appleton WI
    My Bikes
    Several, mostly not name brands.
    Posts
    12,996
    Mentioned
    11 Post(s)
    Tagged
    0 Thread(s)
    I've never bothered with a fixture for the brake bridge or rack bosses.

  5. #5
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,744
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Was there a jig for brake bridges at Trek? I don't remember one, but that doesn't mean anything at this point

    the anvil fixture is awesome, and the Henry James is pretty nice too. Too bad i can't afford either right now. Brake bridges don't bother me too much, but I have problems getting rack bosses the way I want them for some reason. But I have seen plenty of evidence that a lot of people have problems getting brake bridges right.

  6. #6
    Old fart JohnDThompson's Avatar
    Join Date
    Nov 2004
    Location
    Appleton WI
    My Bikes
    Several, mostly not name brands.
    Posts
    12,996
    Mentioned
    11 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by unterhausen View Post
    Was there a jig for brake bridges at Trek? I don't remember one, but that doesn't mean anything at this point
    Yeah, there was. I can see how it's a benefit in a production environment, but for a low volumes there are probably more useful fixtures to spend time on.

    the anvil fixture is awesome, and the Henry James is pretty nice too. Too bad i can't afford either right now. Brake bridges don't bother me too much, but I have problems getting rack bosses the way I want them for some reason. But I have seen plenty of evidence that a lot of people have problems getting brake bridges right.
    Meh. Once you put a caliper on nobody can see the bridge anyway.

  7. #7
    Randomhead
    Join Date
    Aug 2008
    Location
    Happy Valley, Pennsylvania
    Posts
    12,744
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    people are funny about stuff like that. I recall a post from someone that was convinced one of their seat stays was 1mm lower than the other

  8. #8
    Banned
    Join Date
    Aug 2005
    Posts
    5,117
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I think that is to deal with the pre-load one gets from having one side compressed by the drivetrain.

Posting Permissions

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