Thursday, January 19, 2006

CPRR "turned" point spike

Chris Graves has supplied a photograph of one of the extremely rare CPRR "turned" point spikes. He noted that the last order for this type of spike is dated 1872. Spikes with "turned" points, or reversed points, were only used to be driven across the grain of wooden stringers used in open deck wood trestles and bridges on the railroad grade; however they were also used in locomotive and car shops where pits were lined with wooden stringers.

2 Comments:

Blogger CPRR Discussion Group said...

What were the dimensions of the 'stringers' on those old trestles? I visualize a stringer, on top of a tie – why didn't the tie split, when the reverse pointed spike went into it?

—Chris Graves

1/19/2006 12:42 PM  
Blogger CPRR Discussion Group said...

There were no ties on the old "open deck" trestles and bridges. The stringers were originally 7 x 16 and later 8 x 18 inches and spanned the distance between bents of 15 to 16 feet. Why these specific dimensions I cannot say. The rail was laid along the wooden stringer and thus the grain of the wood was also along the rail, thus the spike head had to be reversed to cut across the grain. In a "ballast deck" trestle or bridge, of course, ordinary crossties were employed. Later common standards for open deck structures called for wooden bridge ties, mostly 8 x 8 inch x 9 foot, laid across the wooden stringers and thus ordinary spikes were used to cut across the grain of the tie. ...

—Lynn Farrar

1/19/2006 12:44 PM  

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