A guy at a trade show in Cleveland told me to always run the first part of a new program with the spindle off.

He said it saved his shop from a $12,000 crash on a 5-axis job six months ago, and now I do it every single time, no matter how simple the program looks. Do you have any other cheap insurance steps like that?

3 comments

3 Comments

wesley_grant3323d ago

First time I heard that trick was from an old timer who used to run a Mori Seiki. He had a crash so bad it snapped a shell mill clean off, all because a post processor had a G43 line pointed at the wrong offset. @reed.eva I get what you're saying about dry runs being enough, but there's something about hearing that spindle not spinning that makes you pay attention differently. Its like the machine is telling you to slow down. I actually picked up a habit from that same guy where I always single block through the first tool change too, even on a simple job. Lets you catch if the tool holder is going to smack a vise jaw or a fixture tab before anything moves fast.

willowroberts1mo ago

That's solid advice. What was the specific failure mode on his five-axis job, a tool length miscalculation or a work offset issue?

reed.eva1mo ago

Sounds like overkill for most jobs. I dry run everything in the air anyway, with the spindle on but way above the part. That shows the path just fine. For a simple 2D contour, running with the spindle off is just wasting time. The real insurance is double checking your tool and work offsets before you even hit cycle start.