The first thing to build is the base of the underpart of the windmill. It is made up of 8 pieces with lapjoints to make a octagon. It is called the "onder (under) tafelment"
The windmill was made off oak and I will use the same material. After making some strips of 15 by 6.5 mm I made the lap joints on the table saw
And so I finished the "onder tafelment"