Loading…
1
My lead hand told me to quit babying the roughing passes, and now I can't decide if he was right
Last Tuesday my lead hand watched me run a batch of 4140 parts on the Haas and said I was leaving too much stock for the finisher, so I bumped the roughing feed up 40% and got the cycle down from 14 minutes to 9. The inserts are only lasting about half as long now, which he says is still cheaper than the extra machine time, but I'm not so sure when I'm the one swapping them out. Where do you all draw the line between pushing the roughing pass and burning through tooling?
1 comments
Log in to join the discussion
Log In1 Comment
taylorhunt11d ago
Honestly the part nobody brings up is what those half-life inserts are actually doing to your surface finish and your dimensions on the roughing pass, because if the insert is breaking down faster it's not just a cost per edge thing. A worn insert starts pushing the material instead of cutting it, so your tool pressure goes up, and on 4140 that can mean the part is moving around in the chuck or the turret is taking a beating you won't see until something lets go. Your lead hand is doing the math on insert cost versus cycle time and that math works fine on paper, but he's not the one standing there when a rougher lets go and scraps the part or worse. I'd start tracking your insert wear pattern instead of just counting how many you burn, because if you're getting even flank wear at 40% more feed then yeah he's right, but if you're chipping edges or getting thermal cracks you're just trading cheap inserts for expensive spindle repairs. And tbh the fact that you're the one swapping them means your time is part of that cost too, even if nobody writes it down.
7