First of all, they carve staves out of wood. These are long planks that are wider in the middle. This unique form is important for the future water-tightness of the barrel. There are no nails or adhesives involved. It’s merely staves being carefully adjusted to one another in a metal hoop. Later they would expand under the high temperature and humidity to further cementing of the stave joints. When the sides of the barrel are fixated, they get cropped to one level mechanically. The machine makes crosses for the barrel heads. All the hoops are put in place. It’s necessary to make sure the barrel is liquid-tight. Then it‘s polished and stamped with the brand of the coopery as a final step before delivering it to the distillery or the winery. But before all that ― even before staves take their final form ― they dry. It takes years and affects spirits’ qualities significantly. Therefore, drying conditions must be different for wine and whiskey barrels.