Depends on the railroad. They did or did not for largely the same reasons we would in the garden--cost and benefit for the added labor/expense involved in using them. A tie plate spreads the weight of the train over a greater area of the tie (anywhere between two and three times the surface area). A tie could handle light trains without tie plates. Once the trains got a bit heavier, the passing train would start to really press down into the tie, effectively ruining the tie prematurely. The plates would spread that weight out so to prolong the life of the tie. Tie plates added cost up front, but constantly replacing ties ended up costing the railroad a lot more down the road.
By the 20th century, lines that did not use tie plates would probably have been limited to narrow gauge lines and lightly-traveled standard gauge branchlines. Most standard gauge mainlines were using them by that time because of the amount of traffic. Many narrow gauge lines went their entire lives without ever using them, or used them only in high-traffic areas.
Later,
K
So it's better to use tie plates? Real railroads did, right?
Cost -- availability -- experience -- desire to be "prototypically accurate" in every respect --
I'm just wondering why some people use tie plates when they hand-lay track and other people don't?
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