chucking 6061, grip length, finish tool, and boring jaws

Our 6" machine usually has a collet system and we do 99% bar work but need to put the chuck on and work some 3" Aluminum slugs. I sort of hate chucking due to concern of throwing the part.

Parts are 1.5" long and 3" diam. I am curious what grip length will ensure a good safe run?

Also, there are several radius grooves to be put in on the diam. I was considering trying to run a finish pass with a full radius groove tool, is this reasonable? Finish? Only other way is using 2 tools to reach everything.

Also was considering another option to flip the part but finish diam is about 2.95" and wondering if I bore the jaws for 3.00", could I get away with putting the 2.90" finish diam in the jaws to flip it?

I don't like getting the turret this close to the chuck. not sure what you guys typically do but I just get pucker seeing that turret .25" from the spinning jaws! Anything I can do here to minimize pucker would be great! Hate wasting material though. I was thinking about trying to mirror the part and run 2 which would be no waste but one end tapers to about 1.00" diam WITH a threaded hole in it! That sounds like a no-go to me.

I was trying to think of any way to make a tool or do this differently to minimize waste and keep me away from the chuck a bit.

I should add that this is an easy part BUT my intention is to do it in one operation and not flip it which would include a cutoff close to the jaws. The only reason is to minimize TIR limits by flipping. This chuck is the best. If the part is flipped, it would be rather easy to run and could run with no waste as long as the chuck does not leave witness marks on the finished OD. Not sure if I would have to go to Aluminum jaws for that though.

There is a strict length callout of +/- .0005" and TIR not to exceed .001". Our chuck has wear but I can't remember the last time we bored jaws and tested runout repeatability.

You don't have to cut the jaws that deep to hold these safely. 1/4" is fine. The RPM's might make the jaws open enough to get the part to shift, which would happen no matter how deep they're cut. (Unless you cut a taper in them). I limit my max RPM's to 1500 - 2000 depending on what you can get away with for chuck pressure. You lost me on how this is going to be one operation if you need to finish the diameter you're chucked on, but grooving your O.D.'s and parting off shouldn't be a problem.

0.250 from the jaws ! good grief man I regularly run a manual (with a turret bed stop) to 1/10th of that! ...........and often with only 0.010 clearance.

Check your tool setting and programming, ...........as for boring jaws ?

Do em in pairs and grip by the large flange on the second op in freshly bored jaws, ......the tapered part can go in to the chuck centre hole.

What has been close calls is that we use collet holders in the turret and even though your tool is touched off of the chuck, you can still have a crash from another tool when walking down in X. I think the turret needs reconfigured better then we might loose tool positions. We don't have extension blocks for the OD tools to get the tool away from the turret face and they run right at the same zero as the face. drills and such hang on out there. It is a problem I need to figure out. What we considered doing is boring some tool blocks to recess the collet chucks back in the turret a bit.

This is a minimal issue with the collet nose on the spindle but the swinging jaws on the chuck have before caused things to get all setup just to find out we will have clearance issues.

I just like to minimize crash potential when I can. It tends to get expensive!