I don't know about any of you fellas but there's nothing i hate more than making that first cut with either a new or well sharpened chain only to hit some form of metal object if your lucky it might only be some fine wire but if your not and you've taken large chunks out of your chains teeth ,well it can be costly to your chains life considering the price of some of the larger chains and frustrating ,not a good start to an enjoyable days milling .After doing this a few times on trees that were near farms or urban areas i decided that for the value of a few extra pounds id buy a metal scanner and save on the price of new chains in the long run so i got one like door security would use and its worked great since i got it and added extra life to the more costly larger chains..