1 of my long-time favorite pipes which I've owned and smoked regularly for at least 20 years has suddenly developed a stem too tight problem. Took an hour in the freezer to get to the point I could with much effort wrest the stem into proper position. Now I'm afraid I'll continue to have this problem with it to the point of not being able to use it at all. How in the heck does a pipe have no problem for 20 years and then develop 1? :x