Keilim 20:2-3

Keilim 20:2

A bagpipe is not susceptible to midras impurity. Beis Shammai say that the trough used by masons is susceptible to midras impurity but Beis Hillel say that it is only susceptible to corpse impurity. If a trough from two log to nine kav in capacity (from approximately a quart to about five gallons) gets cracked, it is rendered susceptible to midras impurity. If one left it out in the rain and it swelled up (sealing the crack), it is once again susceptible only to corpse impurity. If one left it out in the east wind and it cracked, it becomes susceptible to midras impurity. In this matter halacha is stricter regarding the pieces of wooden utensils than it is about those utensils in their original condition. There is also a stringency regarding the pieces of wicker utensils that exceeds the laws of such utensils in their original conditions: they are insusceptible to impurity in their original conditions until their rims are finished but after their rims are finished, they are susceptible to impurity even if those rims fall off to any degree.

Keilim 20:3

If a stick was made into a handle for a hatchet, it is considered an attachment vis-à-vis impurity at the time of its use. A yarn-winder is considered an attachment vis-à-vis impurity at the time of its use. If it was connected to a pole, it is susceptible to ritual impurity but it is not considered an attachment to it. If one made a yarn-winder of it, then only the part that is necessary for this purpose is susceptible to impurity. A seat connected to a pole is susceptible to impurity but is not considered an attachment to it. If the pole itself is converted into a seat, only the place where one sits is susceptible to impurity. A seat connected to the beam of an olive press is susceptible to impurity but is not considered an attachment to it. If the end of a beam is converted into a seat, it remains ritually clean because if someone tried to sit there, the workers would tell him to get up so they can do their job.