Keilim 14:2-3

Keilim 14:2

If one affixed a nail to the end of a staff like an axe, it is susceptible to ritual impurity. The same is true if one studded the staff with nails, though Rabbi Shimon says that it is only susceptible to impurity if one made three rows of nails. In all of these cases, if one put the nails in the staff for decorative purposes (as opposed to for use as a weapon), then the staff is insusceptible to impurity. If he put a syphon on top of the staff (as a gasket), or if he put one on a door, it is insusceptible to impurity; if it was a working utensil and he subsequently attached it to the staff, it remains susceptible. Beis Shammai say that the syphon becomes insusceptible to impurity when one renders it unusable; Beis Hillel say when it is permanently affixed.

Keilim 14:3

A builder’s crowbar and a carpenter’s axe are susceptible to ritual impurity; tent pegs and surveyors’ pegs are susceptible; a surveyor’s chain is susceptible to impurity but a chain for tying lumber is insusceptible. The chain of a large pail is susceptible to impurity up to the length of four handbreadths (about 12”), while that of a small pail is susceptible up to ten handbreadths (about 30”). A blacksmith’s base is susceptible to impurity; a saw whose teeth were inserted into a slot is susceptible to impurity but if they were inserted the wrong way, it is insusceptible. All lids are insusceptible to impurity except for those of an urn (and similar utensils).