The front and back of Solid Round Dies and the role of each part

【英】困ったときの知恵袋詳細

Round Dies Metric ThreadsUnified Threads How to useSpecification of toolsBasic Knowledge

I heard that YAMAWA's "Solid Round Dies D" cannot be used from the back side. Can you explain why and is there a way to distinguish the front side and the back side?

In the past, we used to produce solid dies that had chamfers to cut from both sides in accordance with JIS standards.
Because the chamfer lengths and the cutting performances are different for both sides, it was necessary for machine operators to have sufficient knowledge about how to use the dies.
We developed our "Solid Round Dies D" with the chamfer on the front face only in order to improve the overall cutting performance. This change makes it easier for the operator to understand and use correctly. We also added a countersink on the back side to improve the contact surface with the die holder. This stabilizes the machining process with less run-out on the surface.
The front side of the solid round dies D is marked with "YAMAWA" and should be visible when in the die holder.

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