Also, sometimes you just want the stem to vary a bit with the pipe.
+1
Neil’s list gives you an idea of tolerances but no hand maker can intentionally duplicate these figures without a lot of wasted effort. If the button is too high it can feel intrusive in the mouth and too low and it may not feel secure.
It comes down to, do you smoke with the pipe in your mouth (I don’t care for the word
clench but it is descriptive) or do you exclusively hand hold.
Button shape can determine where your teeth imprint. Flat inside walls of the button usually force the smoker to bite onto the button for purchase while a rounded inside wall tends to put the teeth pressure more on the stem. I prefer the latter.
As far as thick / thin, it has to be the smoke hole diameter plus (approximately) two (2) times the thickness of the tolerance of the materials used. Too thin and it may not hold up to the initial bite pressure.
The best button/stem maker I’ve ever seen was
Massimo Palazzi when he was with
Ser Jacopo through the early 1990s (now of
L’Anatra). The buttons were a refined smoothed ridge on both sides that placed your teeth directly on the stem and he also achieved some really thin tolerances that have held up for 30 years to my clenching. The few L’Anatras that I’ve seen don’t show this quality of stem/button work. I imagine that Massimo makes the bowls now so different hands, different result.
Wooden stems of any kind present several problems even for hand holders. The residual taste (
ghost) is burned away when in the bowl but a wooden stem will retain that flavor and you’ll have to retort the pipe many times to remove it. It’s the same problem as too much moisture in the mortise that can retain a persistent taste. Clenching a wooden stem is just silly. Test it out with your dog, he’ll gladly chew it and deposit a nice load of bacteria and possibly breach or crimp the smoke hole. Wooden stems get dull fast and buffing them will misshapen them.