HaO 2011-05-13 The spinbox font may be set using the -font option. In Windows Vista theme, there might appear a gap between the spinbuttons.

pack [ttk::spinbox .s -font {size 20}]

In the clam or alt theme, the style option -arrowsize may be used to change the button sizes:

ttk::style theme use clam
ttk::style configure custom.TSpinbox -arrowsize 20
pack [ttk::spinbox .s -font {size 20} -style custom.TSpinbox]