Go, WeiQi (圍棋), Igo (囲碁), Baduk (바둑) Equipment

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My speculation on how size#s relate to measured thickness is this:

1 shaku(尺) = 10/33m; 1 bu(分) = .01 shaku
white stone thickness for #33 = 1/33尺 = (10/33)/33m
black stone thickness is .001尺 = .1分 less than white
Δ for other size #s = ±.001尺 = ±.1分 = ±(10/33)/1000m

Equipment Dimensions:

dimension JP SI
board length 1.5 shaku 45.45cm
board width 1.4 shaku 42.42cm
table board thickness 1 or 2 sun 3cm or 6cm
floor board thickness 3–6 sun 9.1cm–18.2cm
floor board leg height 4 sun 12.1cm
grid cell length 1.5尺/19 ≅ 7.89 bu ≅23.9mm
grid cell width 1.4尺/19 ≅ 7.37 bu ≅22.3mm
grid line width ≅0.8mm
star point diameter 1 bu 3mm
white stone thickness SPECULATION (see graph above!):
#33 = 1/33 shaku ≅ 3.03 bu[1][2]
Δ0.1 bu per #size[3]
sizes range from #22 to #45
#33 ≅ *(10/33)*1000/33 = 9.18mm
black stone thickness white + 0.1 bu white + 0.3mm
white stone diameter 7.2 bu 21.8mm
black stone diameter 7.3 bu 22.1mm
JP units to Metric conversion
shaku 尺 1 shaku 10/33m = 30.3cm
sun 寸 1/10 shaku 3.03cm
bu 分 1/100 shaku 3.03mm
Footnotes
[1]Size of Go Stones at Kurokigoishi
[2]Wikipedia: Shaku (unit)
[3]rec.games.go: Go Board Dimensions, by Robert Seymour