Quick tip for measuring string from a reel:
Assuming you have a standard length racquet and doing a two piece (While mounted).
Mains: Pull string from tip of racquet to bottom of handle x4 plus the head size. Double that length and you have enough for the mains.
Crosses: Pull string from tip of racquet to bottom of handle x4. Double the length and you will have enough for crosses.
Works for me every time and I don''t have to bother with a measuring tape.
Donnay X-Dark Red 94