Bulmi Craft is a craft technique that produces pots and plough blades with cast iron. Jeju Island has long been self-sufficient in most of its daily necessities and farm equipment due to its inconvenience in trade with the mainland, and Deoksu-ri's French craftsmen are the representative example.

In the form of casting crafts in Jeju Island, there is a hand-pulmu that melts or heats iron with the power of hands, and a thimble that creates wind by digging a goal on the ground, putting a hoop in the middle, and placing a board on top of it, standing three people on one side, as if they were jumping on a board. The hand-pulled radish is divided into two types: tickle and tobull. In Tick-tack-tok-tok-tok-tok-tok-tok-tok-tok-tok-tok- In Tobulmi, molten iron from the bank (Yonggwang-ro) is poured into a pre-made casting frame to make pots, rice cakes, plough blades, etc. Golpulmu is called Golpulmu (or stepping-bubumi or tread-bubumi), and its size and products are the same as Tobulmi, but the way they generate wind is different.

It is highly likely that Jeju's casting crafts led from the simplest structure, Tick-tock-bull-mi, to the Tubul-mi, and to the unsolicitedness of melting the iron by blowing the wind with the force of the feet. Since 1945, Jeju's casting crafts have been declining due to the use of iron pots and cultivators instead of plows.

Song Young-hwa, who is currently a holder of French craftsmanship, continues her tradition of French craftsmanship by holding a reenactment event in Deoksu-ri every October.