Molding System


At BM Fundición we use the most traditional molding process which is sand casting, as this is a refractory material very abundant in nature and that mixed with clay, acquires cohesion and moldability without losing the permeability that makes it possible to evacuate the gases from the mold to the time the molten metal is poured.

Sand casting consists of casting a molten metal, typically alloys of iron, steel, bronze, brass, and others, into a sand mold, allowing it to solidify, and then breaking the mold to extract the casting.
For casting with metals such as iron or lead, which are significantly heavier than the sand mold, the mold box is often covered with a thick sheet to prevent a problem known as "mold float" which occurs when the pressure of the metal pushes the sand above the mold cavity, causing the process to not be carried out satisfactorily.


The precision of the casting is limited by the type of sand and the molding process used. Casting made with coarse green sand will provide a rough texture on the part surface, however dry sand molding produces parts with much smoother surfaces.

For a better finish on the surface of the pieces, they can be polished or coated with a residue of oxides, silicates and other compounds that would later be removed by different processes, including shot blasting.

We have the following methods available:  

+ Self-curing

+ Shell hearts or cold box

+ Sand recovery system

+ Floor Molding

+ Press molding

+ Green sand

+ Mixer

+ Presses with different sizes 

+ Mold handling

+ Floor molding and Mixing mill