high carbon 1/4'' round stock - 5/16'' max. old farm equipment offers some good spear steel. hay rake tines come into mind first off. avoid mild steel and anything stainless. stainless is soft and will disappoint you in the long run. think of it like an old kitchen knife. the Ontario's rusted quickly but, were easy to sharpen and held an edge forever. the crap stainless from China is soft, unreliable and dulls quickly.
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treat your spear like a good quality knife. keep it sharp and clean. dry it when you are done at the end of the day. give it a little oil now and then. keep the tines in a protector when not in the shanty.
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don't grind on the tine tips or barbs after the spear is made and heat treated. only file and stone.
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paint everything else with a good quality paint. blaze orange in case you ''lose'' things like i do.
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engrave some sort of ID onto your spear. some people will steal a good thing.
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