railroad spikes

The spikes used to fasten T-shaped railroad track to wooden ties have an L-shaped head and a square shank. The tip is wedge-shaped, not pointed. The wedge is driven into the tie across the grain, that is, parallel to the track.

Its square cross section gives a railroad spike much higher holding strength than a fastener having the same amount of metal but a circular cross section has; roughly speaking, about 50% more. A spike with the wedge driven across the grain will have about twice as much holding power as one driven with the grain. Early experiments showed that pulling out a 9/16? × 9/16? spike driven 4¼ inches into dry cedar required on average a force of 857 pounds. In seasoned oak, another experimenter needed 4281 pounds.

American, Early 20th Century Length

Length under head (inches)	Width of shank side (inches)	Number in a 200-pound keg
5-1/2	9/16	360
5	9/16	405
4-1/2	9/16	460
5	1/2	505
4-1/2	1/2	535
4	1/2	605
3-1/2	1/2	670
4-1/2	7/16	690
4	7/16	780
3-1/2	7/16	890
4-1/2	3/8	780
4	3/8	1025
3-1/2	3/8	1250
3	3/8	1380
2-1/2	5/15	1650

Ron Holcomb holcombron@hotmail.com Mon Nov 8 12:41:29 PST 1999

Railroad Spike Info from TheForge Archives: Analysis by U.S. Steel: Carbon - .296 % Manganese - .68 % Phosphorous -
.016 % Sulfur - .038 % Silicon - .244 % Copper - .287 % Nickel - .09 % Chrome - .13 % Tin - .001 % Aluminum -
.005 % Vanadium - .022 % Cobalt - .008 %

High carbon spikes were made exclusively starting in or around 1974 to replace the low carbon spikes that were generally just iron and carbon (with a couple trace elements thrown in for special areas).
For High-Carbon Steel Track Spikes: Steel was made by one or more of the following processes: open-hearth, acid-Bessemer, electric-furnace, basic-oxygen.

Chemical Composition: Acid-Bessemer Other Process Carbon, min. percent 0.20- 0.30 Copper, when specified: 0.20%

Tensile Properties: Tensile Strength, min. psi. 70,000. Yield Point, min. psi. 0.5. Tensile strength Elongation in 2 in., min percent 25 From: Machinery's Handbook

Ron Holcomb holcombron@hotmail.com Mon Mar 27 11:00:05 PST 2000

Note: One should not assume that these spikes are considered to be "high carbon" in the usual sense of the term. The spikes will not contain more than 40 points (.40%) of carbon and, therefore, will not (in my opinion) respond to heat treatment in such a way as to make a proper knife edge.