Purpose of reference angle design:
1. In order to ensure machining accuracy of workpiece, it is necessary to take data from same direction for each process during multi-process processing, so workpiece needs to design a reference angle;
2. Design of auxiliary datum is indispensable for local features of workpiece that can only be processed by CNC or EDM after workpiece is placed at an angle, it plays role of processing and taking data;
3. In order to have a detection origin when workpiece is detected, a datum needs to be designed;

 

In order to distinguish reference angle of each mold plate, we need to chamfer large C angle on the reference angle side for identification. Chamfering standards are as follows:
A. Reference angle of mold base less than 500 is chamfered C6;
B. Reference angle of mold base greater than 500 and less than 1500 is chamfered C10;
C. Reference angle of mold base greater than 1500 is chamfered C15.
Chamfer after increasing specifications on each mold plate is reference symbol of our mold plate.
At the same time, in order to facilitate reference at a glance in later stage of mold repair on client, on the basis of chamfering reference, it is required to engrave "base" character on reference angle side of all AB plate parting surfaces
1. This requirement is only for AB plate parting surface side, and other mold plates are not required;
2. AB plates of original and embedded molds must be engraved with base character;
3. Front and rear mold cores of embedded mold do not need to be engraved with base character.
Based on actual situation, it is specially defined that workpieces and features in following situations need to design a reference angle:
1. All glue positions;
2. Local features of workpiece that can only be processed by CNC or EDM when workpiece is placed at an angle need to design a processing auxiliary datum;
3. Each mold plate of mold base;
4. In principle, all molds take data on one side. Hereby, we formulate reference angle design specifications for workpieces!

 

a. For all AB plates left in original body, four corners on mold parting surface side must be designed with a number plane. Number plane is designed with reference to lower right figure:
b. For front and rear mold cores of mold, there is no need to design a number plane at four corners. Workpiece is directly processed from large water mill to fine material number.

 

Design specification of code screws for AB plate processing

 

e. An M20 screw hole should be designed near four corners of bottom surface of cavity & core. This hole is used to lock shim with screws during processing. In this way, only shim needs to be pressed with a code during processing.
This code tightening method allows internal stress of workpiece to be released freely during processing. Although workpiece is deformed, processing accuracy of parting surface side can be guaranteed. Finally, bottom surface of workpiece is finely processed based on parting surface side, thereby effectively solving problem of deformation of steel after processing.
f. Original process requirements for processing code groove on the side of workpiece are also cancelled.

 

 

 

When designing reference angles of long strip parts, because workpiece is long, if reference angle is designed too short, it will cause inaccurate machining calibration. In this case, we will design two reference planes in the same plane in long direction of workpiece, as shown in green mark on the left.
When designing reference angles of long strip special-shaped parts, because workpiece is long, if reference angle is designed too short, it will cause inaccurate machining calibration. In this case, we will design two reference planes in long direction of workpiece that are not in same plane but parallel to each other, as shown in green mark on above figure.

 

 

When workpiece needs to be placed at an angle, local features of workpiece can be processed by CNC or EDM, and processing auxiliary datum needs to be designed.
Green marked surface in circle in figure below is processing auxiliary datum for core hole of workpiece.
Design of processing auxiliary datum should be able to be directly processed without placing workpiece at an angle, so as to ensure accuracy of processing auxiliary datum angle.

 

a. For bumper top mold, because workpiece size is too large, it is also necessary to design number level as reference for processing at four corners according to figure below.
b. Adjacent references should be designed on same plane first. Value from reference plane to mold center should be an integer, not a decimal.
c. Front and bottom of workpiece also need to design number box shown in figure.