chair mould

How you make the parting line finishing is good, if there will is any sharp edges?

Sharp edge on the chair is dangerous, in order to avoid the sharp edge, we have to do many points during the mould manufacturing. - chair mould parting design is correct or not. - the cavity and core thickness is enough or not. - how you make the CNC milling the cavity and core? One stage finishing or several stage finishing?

Normally, we need 3 stages finishing. From rough milling to steel hardened, after hardening, take the 2nd stage milling, we call it half precise milling, normally we leave 0.3mm, Then make the steel stress releasing, after this we do final precise milling. When in this time, the machining operation is very important.

1. we have to use cooling on the milling area. 2. we have to be sure that each cutting, the depth will not bigger then 0.08mm. All these are because of the steel will be deformed when milling and after the hardening. The deforming will cause the cavity and core’s fitting are not accurate, there will be a lot of hand works on it.

By hand works on the parting area, you can never work out a perfect parting line.