well its possible... but its gonna be pretty difficult...i would not reccomend starting with a rail spike. Some of the spikes MAY be high carbon steel but getting it to the thickness is alot of work especialy if you have never forged before. My advice would be to either get some basic stock like round stock and hammer it flat (dont get it very thick) OR get flat stock the thickness you desire and cut it out with a hacksaw or other tool. Straight razors are one of the finest edged tools that a common person would use on a daily basis. They require a great first sharpening and then great maintence following it. I have taken a qoute from another article on this to share with you.



'Sharpening is the final stage in the process. At first the blade is sharpened on a grinding wheel. Following that the blade can be honed by holding the blades against the flat side of rotating round stones, or by drawing the blade across stationary flat stones. The cutting edge is finished using a strop."



So the idea behind it would be to go from a quick edge using a somewhat fine grinding wheel on your grinder or a stationary stone. Be carefule in doing this cause excessive heat that can turn the steel colors is bad for the integrity of the blade. The you would move up to different courseness of arkansas stones until you get it pretty fine. Then from there you would use a strop possibly with polishing compound on it to finish the edge. You may be able to get a shop to do it for you but make sure to discuss the use of the blade with them before having them do it so you know what they are able to make the blade do. I have a railroad spike knife myself and let me tell ya..with a good amount of work its still pretty thick..id call it more of a chopping knife due to the thickness.