Wax pattern making is very important in the process of lost wax casting process.The quality of wax pattern will have directl influence on lost wax castings.Below are the introduction of common defects and solutions for wax pattern when making.
1.Deformation of wax pattern.After getting wax pattern from mould,sometimes deformation is casued by workers' wrong operation,in addtion to size change narrow itself.Because it is common that wax pattern flexure deforms in the cooling process,so we should keep it carefully placed from pattern.Also too soft wax material,unreasonable design of mould could be a factor for deformation.
2.Wax is not fully filled into mould.Main cause is the temperature of wax material is too low.For low molding temperature and injection speed,then wax is not totally filled in the edge and corner parts of mould.
3.Wrinkles on the surface of wax pattern.
4.Wax mold surface depression,mainly becasue the injection pressure and time is not enough,or wax material at higher temperature,cooling time is not enough,sometimes too much mold release agent.It would be be difficult to repair if surface concave involved is relatively large,easy to cause waste.
5.Seam exist in wax patterns,this is one of the most common defects,namely in the pressed close type,pressure type combination of joint,the joint of core and core city and other places have very thin slices of wax to escape.The reasons are mainly molding precision is not enough, pressed parting surface or within a joint surface damage or impurity attached,or rated-locking force is not enough, the injection pressure is too high.Or wax temperature is too high. Wing must be thoroughly cleared MAO,wax models can be used.
6.Wax pattern and molding adhesive,this is because don't use the mold release agent, or wax and molding temperature is too high,or is pressed inside surface clean.
7.Rough surface of wax pattern,as pressure is too low, or low speed of injection. Then material contact with the inner surface of molding density is not enough,serious still can appear fold.