Running into a dilemma…
I have no trouble ending up with an accurate finished part with really tricky features.
BUT…BUT I can’t figure how to quickly develop a roughing strategy. I’m always doing short run items so I don’t have many opportunities to be hogging out material repeatedly. So, when I get a 1pc job that needs a lot of material removed, I’m very slow.
To a point, where I’m getting micromanaged… on roughing.
I’m inclined to be safe and prioritize process stability over Material removal rate. For example in HEM, Instead of doing 10% stepovers, i’ll do 6%. In turning, I’ll keep DOC down on the bottom left end of recommended specs instead of burying past the insert radius. I don’t get off on huge MRR like others, my moment of glory is hitting incredible tolerances on a difficult design/material.
What really scares me is… that a mistake in roughing parameters comes with bigger risk than just “tighten the bolt until it loosens up and quarter turn back”. It’s the part becoming a projectile/scrap, machine damage, and at worst an injury. Lathe work where I have only a fraction to hold onto and inches of material to remove…
How have you developed a ‘sense’ for how aggressively you can rough?
I’ve been working as a prototype machinist for a few years so similar situation.
You just gotta try. If the tool says it can do it and the machine has enough power just work up to a good DOC. Trust the DRO and have at it. I’ve almost never had anything go flying out of a vise or chuck, but use good judgement.
I’ve made .1" doc in 17-4PH H900 and titanium on the lathe holding onto 1/4" of material. Never had a part go flying. Ive thrown parts in the mill but never caused machine damage, just broken endmills and scrapped parts.
On super expensive material or parts I’m slow but I can still hit .0001" tolerances with big roughing cuts.