JV,
Not 1/4" (quarter-inch) of english, 1/4 of a tip, a pool convention that is a tiny increment. For a 13mm tip, 1.65 mm (a tip is one half overlap of itself, so a 1/4 tip is 1/8 of a typical 13mm tip, or 1.65mm over to the right with the tip).
Also, I have free space, like most players, in...