A collision caused by a wrong offset, a program error, a missed tool length, a vise in the wrong place or a human hitting the wrong key. Small crashes break tools and scrap parts; big ones knock the spindle out of alignment, ruin bearings and shift machine geometry, costing thousands. Every machinist has a crash story, and the first thing after one is checking spindle runout.
Wrong tool length on T7, it crashed straight into the vise at rapid, so check spindle runout before you call it fine.
After any crash, indicate the taper and check spindle runout before running another part, even if everything sounds normal.
Also heard as
- wreck
Related terms
Feed hold
The CNC button that stops axis motion instantly while the spindle keeps running.
Prove out
To run a new CNC program cautiously the first time, watching every move to catch errors before they crash.
Touch off
To set a tool's position by bringing it to a known surface and recording that point in the control.
Work offset
The stored distance from machine zero to the part zero, so a CNC program runs from the right place.