Buck 4862 6-jaw chuck reassembly/cleanup

perimeter of the cavity. most will be flung by centrifugal force.
Gotcha. I had previously figured that since they can't get out of the cavity it doesn't make a difference, but yeah good point. The chips in my "before" pictures do show oil doing the thing you'd want them to do. I'll keep this in mind for other chuck servicing I'll be doing soon as well as whenever I get into that 6-jaw again. It won't see much use so this isn't a huge deal in the meantime
 
Not to disagree but most/many of us use grease behind the scroll and oil on the scroll and jaws. I've been doing this for decades and haven't had a problem with chips migrating into the cavity behind the scroll. Then again, I do maintain my chucks. Maybe in a busy shop that never cleans their chucks this might be a problem.
 
Got it mounted up on a back plate. I left a couple thou of space on the register of the back plate for adjustability, and it turned out to be the perfect amount to get the chuck dialed in. Testing on 1/2" end mills, I got signs that this is repeatable to at least as good as .001" -- works for me! I will need to skim and flip some parts at larger diameters to gauge if it's repeatable across a range of sizes, or if I just happened to dial it in for the wear when clamping 1/2"

Either way I imagine it should be good within a few thou based on how good the internals looked when I had it apart.

The biggest issue with it is that it clearly has had rough life, dropped a few times -- the body is kinda beat up but as far as I can tell the face of the chuck body will pretty much never be a reference surface on here so the dings around the corners have no bearing on functionality

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I believe you could take a light facing cut on that chuck without the jaws. it should help to give you a flat reference face.

I use my face to set the qctp square, so I need it..
 
Well as I tested with other diameters of round stock, took a skim cut, and flipped it - it looks like this is not as repeatable on other dimensions, like .010 to .015 variation; At least not while it's zeroed in for 1/2". I'll need to do a few more tests, my first one was flipping a part that I skimmed at both ends, but they were substantially different diameters -- so that isn't technically measuring the repeatability at a single dimension.
 
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