ALL THE TOOLTIPS ARE WRONG!
This is obtained by Heating Standard Timber Squares(chopped scantling(chopped logs)), and Plywood Hardener.

Измените рецепт. Требуется 10 Древесины и 3 Укрепителя для фанеры

The recipe requires 3 Plywood Hardener not 1

You need Skilled Heating to be able to make this item. The quest can be started here:

http://bdocodex.com/th/quest/3208/1/

Requires Skilled 10 Gathering and Professional 5 Processing to start, and leads to a Skilled Chopping quest. The NPC villager is next to the arms dealer in Keplan. Preparing all the materials beforehand will make everything much smoother!