1 - If you buy regular scissors that are made for cutting paper, and use them for cutting open ices ( igloos ), or other foods, Does it require Tevila ? ( 75B ) 2 - The gemarah and halacha ( 76B ) state the concept of Kashering a knife for cold by sticking it into the ground ten times, Where is the source for the well known custom of leaving the knife in the ground for 24 hours, many people will tell you that they have utensil gardens from all the forgotten utensils placed in the ground and forgotten there ?
1. A utensil that is not specifically intended for use with food does not need Tevilah, even if it is occasionally used for food. If it is designated for use with food, then it does need Tevilah.
2. We could find no source for the custom to leave the knife in the ground for 24 hours. It is a common Minhag among Jews of Hungarian descent. It is probably related to an additional stringency that the Ta'am Shel Isur that is absorbed in the knife be a Ta'am li'Fgam, which, for most foods, is accomplishing by leaving over the utensil for 24 hours without using it.
BTW, Rav Pam zt'l in Yorah Deah shiur said that rubbing with steel wool was as good as neitzah b'karka.