Siemens alarm 61951: Cutter radius for residual material too large

What it means

In residual-material machining the follow-up cutter may not be larger than the reference cutter that produced the rest material; otherwise it would re-enter regions still holding uncut stock in unpredictable ways. The cycle checks this relationship and aborts. Use a follow-up cutter with a smaller radius.

Likely causes

• Residual cutter diameter >= reference cutter diameter
• Reference-cutter radius changed in tool data after program creation
• Wrong tool selected for the residual pass