Manual modeling is still the important methods, manual modeling can adapt to the requirements of various complex is more flexible, does not require a lot of process equipment.Can be used sodium silicate sand, sodium silicate sand mold VRH law, organic ester sodium silicate self-hardening sand, clay self-hardening sand mould and dry type, resin cement sand mold, etc.;Lost wax casting for single production of heavy castings, pit modelling method of low cost, fast production.Batch production or long-term production of finalize the design product box, split box shape modelling method is appropriate, although high mould and sand box to start investing, lost wax casting thought from the aspects of modelling man-hour saving, improve product quality.