Method for forming bicycle frame assembly with integral fastener passage
A method for forming a bicycle frame assembly having a number of elongate tubes is disclosed. A two part mold can be used to form a hollow finish part as part of the assembly. The assembly includes a passage that is defined by the elongate member, a partition, and a bridge. The partition isolates the passage from an interior volume of the elongate tube. The bridge extends in a direction normal to an elongate direction of the passage and defines an inlet and an outlet of the passage. The inlet, outlet, and bridge are generally flush with an exterior surface of the elongate tube and provide a passage that cooperates with a flexible connector, such as a cable tie, for securing supplemental structures, such as brake and shift control cables, to the elongate tube of the bicycle frame assembly.
1. A method of forming a bicycle structure comprising:
providing a mold having a first mold half and a second mold half that cooperate to define a cavity that defines a majority of an exterior surface of a hollow finish part when the mold is closed;
providing an insert that cooperates with at least one of the first mold half and the second mold half and which is positioned in the cavity when the mold is closed, the insert having a curvilinear arm defining a passage curved along a longitudinal axis of the passage that extends through the hollow finish part and is defined by a partition that separates an interior volume of the hollow finish part from the passage and from atmosphere and a bridge that defines an inlet and an outlet of the passage;
introducing a material into the mold;
forming the hollow finish part; and
removing the formed hollow finish part from the at least one of the first mold half and the second mold half such that the inlet and outlet are exposed to atmosphere, separated from one another by the bridge, and are flush with the exterior surface of the hollow finish part.
2. The method of claim 1 further comprising providing a collapsible bladder in the mold that defines the interior volume of the hollow finish part.
3. The method of claim 2 wherein the collapsible bladder is positioned in the mold prior to closing of the mold.
4. The method of claim 1 further comprising passing a flexible connector through the passage so that the flexible connector is secured to the removed formed hollow finish part via interaction with the bridge.
5. The method of claim 4 further comprising securing a structure to the removed formed hollow finish part by engaging the flexible connector with itself so that the flexible connector encircles the structure and the bridge.
6. The method of claim 1 wherein the forming of the hollow finish part further comprises injecting a carbon fiber material into the cavity after the mold is closed.
7. The method of claim 1 further comprising shaping the cavity of the mold so that the hollow finish part forms at least one of a top tube, a head tube, a down tube, a seat tube, a chain stay, a seat stay, and a fork leg of a bicycle assembly.