Fishplates are implements used to join the ends of rail lengths. While rail lengths are produced in the largest possible dimensions to minimize butt-jointed ends, the need for connecting hardware is inevitable. These rectangular bars and plates feature several holes, through which two rails are bolted together to create a continuous track. Fishplates are a poor conductor, so track circuits require electrical wiring. Undoubtedly, the seam between rail lengths is the weakest portion of the track — even when using fishplates — and supplemental welding is often utilized. Also known as joint bars, fishplates earn their name from a similar item used to join sections of mast on wooden sailing vessels.
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