The buildings where the flour mills are housed respond to the same typology: they are mostly constructions of very elementary structure and built with low quality masonry with granite ashlars in jambs, lintels and corners, generally cemented on rocky places from the banks of the rivers. The most usual plant is rectangular, with no more gaps than the access door or some small window, gabled roof and brick vault.
They consist of two heights with little communication between them, the lower one contains the rodents and the passage of the water with exit openings in the shape of an arch; in the upper floor or grinding room, and we find the crushing mechanisms. The mills by domestic flour mill manufacturers can have from one to five stones or stops depending on the demand of grain and the flow of water available.
In a mill we can distinguish the following parts:
Hydraulic installation: located on the banks of the rivers and taking advantage of places with some unevenness, these mills by plan sifter machine suppliers capture the water upstream, diverting it with a dam or dam to a channel that leads to a fishery where it is stored. In the way of driving the water to the Rodezno, we find two types: on the one hand those that do it directly through a ramp or bacon channel; on the other hand, those who use a cylinder or bucket up to twelve meters high to achieve a greater thrust of water. Once the small gate or the arrow is opened, the water hits the paddles of the rodezno making them turn and transmitting the turn to the stones of the upper floor through an axis or tree. Later the water follows its course and is returned to the river by the cacao.
Rotation mechanism: it is basically composed of two elements: a wooden or metal wheel with a series of blades called rodezno that receives the thrust of the water and rotates horizontally; and an axle or tree composed of an upper part of iron or sword that crosses the lower stone to be joined to the upper one by means of the lav that fits in the mobile wheel dragging it in its turn; and a wooden inferior that fits in the rodezno, called maza.
Mechanisms of Molturation: consists of two cylindrical stones, the molars, with a central opening. The upper or volandera is mobile and its turns on the bottom or sleeper (stays fixed) cause friction to grind the grain. The cereal is stored in an inverted truncated-pyramidal wooden hopper to gradually fall through the central hole between the grindstones that turn it into flour that ends up in a wooden or wooden drawer. There was the possibility of regulating the thickness of the flour by varying the separation of the stones by means of relief. Every so often it was necessary to lift the flying wheel to chop it and renew the internal grooves with the help of a pickaxe.