In the process of precision casting, both small parts or machine structure, we do other must to die after parts of repair type, there are many kinds of methods to repair, today we to four kinds of modification methods,
1, the parts in the mold after local soft false place for trowel loose and tool ramming.
2, two pieces of jade intersect with the damaged part can be used to trowel stick on the sand and the sand felt gap and smoothing.
3, with I out of the sand can be re painted mud water re repair,
4, the area is relatively large, but not deep groove should dig out some again.