What Is a Button Die?
A button die is a component used in the lower die plate of a mold for nesting. It is designed to be easily removed, polished, and replaced, allowing for prolonged use and maintenance. Typically used in die plates not subjected to hardening, button dies facilitate easy fabrication and maintenance of dies.
Uses of Button Dies
Button dies serve as crucial parts in die plates for creating and finishing holes, especially in non-hardened materials. They are integral to the drilling process, acting as the lower blade while the punch serves as the upper blade. Their design allows for the removal and regrinding of worn blades, enhancing longevity and performance in hole processing.
Principle of Button Dies
The button die is the part of the blade that needs to be hardened to prevent wear. However, the lower die does not need to be hardened.
It can be processed by punching. During processing, it is necessary to penetrate the hole so that the cut shavings can fall as a countermeasure against hole jamming to avoid the punch breaking and damaging the product. In addition, the remaining processed shavings may fly out of the surface of the button die, and if processed in this state, dents will remain on the product, so care must be taken.
Structure of Button Dies
The hole in a button die consists of a relief section and a land section, and there are three types of cross sections. Some button dies have a tapered land section to allow the material to pass through. The disadvantage, however, is that the hole gradually becomes larger during regrinding.
There are also button dies that have a straight section where regrinding is required, so that the dimensions of the hole do not change during regrinding. On the other hand, button dies that do not have a large relief at the bottom of the land area, but instead have a straight land area with a tapered relief at the bottom, are called angular button dies. Angular button dies are easy to use for pulling out small-diameter holes, taking into consideration the possibility of clogging.
Types of Button Dies
Button dies come in various forms, including straight and standard types with collars, and are made from materials like powdered HSS, cemented carbide, SKD11, and SKH51. They are designed to fit into plates either with a press-fit or using spacers for adjustment, accommodating regrinding without altering hole dimensions significantly.
Selecting a Button Die
Selection depends on the ability to regenerate cutting edges through regrinding. Considerations include the method of regrinding (whole plate vs. nested parts), ensuring evenness post-polishing to avoid quality issues, and adjusting the “L” dimension for optimal performance, especially in preventing clogging for small diameter holes. Proper adjustment and selection criteria are essential for maintaining quality and efficiency in drilling operations.