Surface roughness and surface roughness obtained by different machining methods

Here, the "Surface roughness and surface roughness obtained by different machining methodsI am making a note about ".

Surface roughness and surface roughness obtained by different machining methods

Mechanical Drawings　In order to determine the surface roughness (surface roughness) to be described in Section 3.1, it is important to know how much surface roughness can be obtained depending on the processing method and to specify a surface roughness that is generally easy to obtain and does not cause problems in the processing.

Table of surface roughness and surface roughness obtained by different machining methods

Below we share a table of surface roughness obtained by different machining methods. In this kind of general tables, there is only "Ra" description, but the following table also shows the relation with "Rz, Ry, and old finishing symbols". (Please refer to the supplementary rules for Rz and Ry.)

The above table is a combination of the Mechanical Design and Drafting Handbook "Table 6-19: Roughness ranges obtained by various machining methods" and "Table 17-26: Surface roughness classification of finishing symbols" and "MISUMI: Relationship between arithmetic mean roughness (Ra) and conventional notation".

Supplement: Rz and Ry (maximum height roughness)

Rz and Ry in the above table are defined in the standard "JISB0601: Geometric properties of products (GPS) - Surface properties: Contour curve method - Terms, definitions and surface properties parameters

• Old = Ry (JISB0601:1994 and JISB0660:1998) *Rz at that time was defined as 10-point average roughness.
• Currently = Ry ⇒ Rz (JISB0601:2013).

for that reasonThe table above lists two types.

[Supplemental] There is actually a standard piece that can be purchased.

I have one, though,Flat Surface Roughness Standard Piece" by Nippon Metal Denchikuis useful for design reference, so if you don't have one or didn't know such a thing existed, please refer to it.

That's it.