Vise Jaw lift, is there an adjustment on PM vises?

Oh, foo, minor disaster. I was taking off 0.005" at a time, everything went well until the mill hit a hard spot or something. I had taken off 0.035", 0.005" at a time, without a problem. The surface was ok. When the mill hit the hard spot, it dove in and pulled the piece up from the vise about 0.100". Exciting in a bad way. There's plenty of meat left to take out the somewhat cylindrical divot, but it is disappointing nonetheless. Coming in that way should not be climb milling right? Normal rotation, workpiece to the left and cutting from back to front? I wasn't even near the end, where I would slow the feed rate. My feed rate was really slow, by the way, like about 0.5" per minute. I really was taking it easy. Once I slow my heart down, I'll go at it again.
PXL_20210414_193158273.jpg
Ball came out nice, first pass. I have 49 extra of them, but only 1 nut, so I have to rescue the nut.

Obviously did something wrong, what was it? Not eager to make the same mistake. Milling 0.005" but with 1.5" LOC?
 
Based on the previous image, you need to cut from the 'inside' out to not be climb milling. That is too bad, but it seems you have enough material to make it happen. _IF_ it gets too bad, you can always loctitle/glue on a shim of some sort to space it out, so as long as you don't go TOO far you're ok.
 
The way it grabbed would seem to be climb milling, but the picture I have, would indicate it wasn't. I'm confused...
The mill was talking to me - it was kind of squeaking at times, even though I had put cutting oil on the mill and the workpiece.
PXL_20210414_202828333.jpg
 
That diagram is awkwardly configured, at least to me. The arrow is the direction of the workpiece in relation to the mill. So you would have to start your cut from the 'bottom' in that picture (near the operator) and pull the material/table toward you to get a standard cut.
 
I should say so. I apparently have been doing it wrong from the beginning, due to that drawing. This is the first time, I've been burned, which, if I think about it, is pretty amazing.

I found a better picture on Harvey Tools that describes normal and climb milling.
Normal:
1618432923419.png


Climb:
1618433013901.png

I still find these pictures confusing, since my mill rotates CW, not CCW. Why draw it as a mirror image?

But I have now learned I have done everything backwards :chagrin: I need to make my own picture, that even I can follow.

Climb is fat to skinny. Standard is skinny to fat... That was a tough lesson. Ok, back to work...
 
I like to think of whether the cutter is pulling itself into the uncut region (climb) or pushing back from the uncut region (conventional). Then think about a full-width slot and it’s neither.
 
Yeah, that harvey pictures is odd, I don't know why they would do a 'bottom' view!

I always considered it like the flutes were 'swimmers' arms. When they are trying to pull the material with them, like a swimmer, that is 'climb' milling. When they are trying to swim 'against' your feed,that is conventional milling.

So on a normal clockwise (from the top) spindle, clockwise around the material is 'climb', counter clockwise around the material is conventional.
 
I always think of it as "am I traveling with the flute, or against it?". Which has been pretty foolproof.
 
Well, it's done. More or less recovered from the climb gash. Tiny divot on the edge, nowhere near the ball. Tried setting up the movable vise jaw in my toolmaker's vise, but it wouldn't fit the way I wanted to hold it. My toolmakers vise needed about 0.100 more travel. Kind of gave up on that. Tried some grit in the pocket to smooth things out but the throwaway ball bearing was too slick for me to rotate it all that much. After a while, I just cleaned out the pocket about 4 times, then decided I was going to put the vise iall back together. Greased the half sphere and the ramp surface. The lift is slightly lower than before, but I was getting a little tired at that point and sloppy with the measurement. I have to go back and look at my notes on my initial measurements, to see if there was any improvement.

The good thing - learned a (hard) lesson about climb milling. I also have a working vise again. Here's a picture of the mostly recovered nut.
PXL_20210414_233131967.jpg
I'm going to say, I'm not going to knowingly set up milling that way again. It was like working blind because my vision was obstructed. I had to go by sound and feel - which is good, I guess, but I sure wasn't comfortable machining that way.
 
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