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  1. #1
    30mi/day commuter
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    making a drop bolt (one sided?)

    can I make a drop bolt that is a single plane of metal or do I need to make 2 metal pieces come down and have washers of something in between?

    I imagine the only issue with one peice of metal would be the torque on it during braking which wouldnt be shared by 2 peices of metal.
    But it would be a lot easier to make... ill just use like a 1/4" peice of aluminum i figure.

  2. #2
    Gear Hub fan
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    You can do so as the factory ones I have seen photos of have been one piece of material. You need to make it thick enough so there is minimal flex and to me that means thicker than 1/4" aluminum IMO. I would use steel for thew added rigidity. Also you want it thick enough so that the caliper mounting nut can tighten against it.

    Personally I would prefer to fit longer reach brakes as drop bolts indicate use of incorrect size parts for a bike build, at least to me.
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  3. #3
    coprolite fietsbob's Avatar
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    As you can see on reply to your other post on this topic, drop bolts have a groove in them for anchoring the return spring.
    As they replace that part of the center pivot brake,
    it is more than a piece of metal with 2 bolts facing in opposite directions, in it.

    As several have said, get a brake with a suitable reach.

  4. #4
    Old fart JohnDThompson's Avatar
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    Sheldon Brown offers one home-brew solution: http://www.sheldonbrown.com/home-drop.html

    I made one out of a piece of electrical conduit:

  5. #5
    Senior Member DannoXYZ's Avatar
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    I think we're talking about two different things. The traditional drop-bolt replaces the centrebolt of the brake with an offset one to lower the caliper arms (works well when you only want a modest-drop, like 10mm):



    If you need more drop than that, then there's sufficient room to create a drop-bracket that lets you mount the same brake lower. In these cases, you MUST make them double-sided to deal with the single-shear cantilever forces:




    Due to the wider bracing, you can use thin material, 3mm steel or 5mm aluminium. If you want to make a single-sided one, I'd go with no less than 10mm aluminium.

  6. #6
    pmt
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    Here's one I did. Works nicely with no problems.

    IMAG0071.jpg

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