Specifications
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 CONCISE GUIDE FANUC 37 
3.12 “G41”-“G42”- “G40” TOOL RADIUS OFFSET  
All inserts for turning have the cutter edge rounded to a pre-defined radius, specified by the insert 
manufacturer (e.g. 0.4; 0.8; 1.2 etc.). With the tool measurement a point is determined for movements 
that is not on the insert profile, but is the intersection of the horizontal and vertical lines tangent to the 
insert radius, as can be seen in the figure that follows. 
This difference has no influence when turning cylindrical parts at 90° but causes an error when machining 
conical and /or spherical parts, creating a profile that is not the same as that programmed. The value of 
this error is proportional to the insert radius and assumes the maximum value in the case of a conical 
profile at 45°: 
Error = 0.412 x Insert radius 
La tool radius offset è attivata e disattivata nel programma mediante le 
seguenti funzioni: 
Insert 
Turned 
Profile 
Programmed 
profile 
Insert 










