What is the difference between router bit’s quality grade N, A, AA and 3A ?

Router bits can be called as router cutter or cnc engraving and milling tools also. There are four quality grades on router bits, which are N grade, A grade, AA grade and 3A grade. Actually the bits’ grades are distinguished by the material. It’s the only difference. For example, N grade Router bit is made of N series material; while A grade bit is made of A series material. The same to AA and 3A.

Please see full explanation of different series of material in below,

All the bits are made of tungsten material. N, A, AA and 3A are the grades of tungsten material.

N Series material is tungsten steel from China Mainland, hardness is at 88- 89HRA.

(HRA means hardness Rockwell A scale)

A Series material is Taiwan’s Chunbao tungsten steel, hardness is at 90-91 HRA.

AA, 3A Series materials are Germany’s ultrafine particles tungsten steel material, AA’s hardness is at 93-94HRA, 3A’s hardness is around 96HRA.

The better material means the higher hardness of router bit. Service life of the bit depends on the hardness of the bits.

The higher hardness means the better finishing of job. To get better finishing, please choose bit with higher hardness.

The finer tungsten steel’s particle means the sharper polished edge of router bit. To get better finishing, please also choose bits with finer particle tungsten steel material.  

In a word, better material of router bit gives better finishing and longer service life. 

A small tip, when order the router bit; please clarify the material grade you want. If no request on it, default material is N grade.   

From www.eaglecnctec.com
Jinan EagleTec CNC Machinery Co.,Ltd.