Tool nose radius compensation (TNRC) – what is it ?
Does machining such parts make you angry, confused, frustrated ?
TNRC, or Tool Nose Radius Compensation, is a must for parts like the ones shown above. TNRC is easy to implement in your CNC programs, but a much misunderstood and misused concept on shop floors.
We’ve all encountered these problems some time
– Our competitors are able to do such parts, but we have to turn them away.
– Contours are not matching, and we get a line between a taper and an arc.
– We’ve programmed a 0.5 chamfer, but getting no chamfer at all.
– We’ve produced a batch of parts involving ball turning, and the whole lot get rejected.
And we’ve probably done one of these
1. Got it right after trial and error, wasting a lot of raw material and machine time.
2. Given up on the part, or sub-contracted it out.
3. Blamed the machine, called the machine manufacturer.
The correct solution is to use TNRC, which means in effect doing these
1. Add TNRC commands in the program.
2. Enter the nose radius of the tool at the machine
3. Enter the tool orientation at the machine
This short explanation on TNRC tells you what it is, where it is used, and how it’s poor understanding causes agony on most shop floors. It will help you understand TNRC, and/or pass on the knowledge to people on your shop floor.
The three TNRC steps listed above are of course to be done by people, and people forget, and people make mistakes, and people change. If you would rather be system-dependent than people-dependent, CADEM CAPSturn CNC lathe programming software takes care of this headache for you. It directly generates NC programs with tool nose radius compensation, and there is no need to enter TNRC commands in the program or any data on the machine.
