Carbon Steel Square Thread Rail Spikes

Railway track spikes 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"railway track spikes driven 4¼ inches into dry cedar required on average a force of 857 pounds. In seasoned oak, another experimenter needed 4281 pounds. Below is the technical data of dog spike.

 

The bottom of the head is sloped to match the slope of the flange of a rail and the tip is wedge-shaped, not pointed. The wedge is driven into the tie across the grain, which means the wedge is parallel to the track. The square cross section gives a railroad dog 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.