Choice of tool

[Steve Walker]

Plane them flat enough to fit through the new Royal Mail slot, and stick a stamp on 'em... :o)

[Ed Sirett]

The over-whelming majority of house floorboards are still sold in the original sizes. There are just a few houses (my own being one of them) where an unusual thickness was used. In my case I used 15mm MDF to get a good match on the thickness.

[Stuart Noble]

Most timber merchants will thickness boards for not much money