Question about cutter height on a lathe

BTW,

"Close enough for government work" used to mean done to a very high standard. People got serious about getting things right when messing up on a part could mean one of our soldiers not making it home....

Cheers,

John
 
The important takeaway here is that there are a number of ways to set tool height. They all work to a lesser or greater degree. I use at least four of them, the choice depending on the particular task at hand.
 
After thinking it over, it seems like the best setup (for me) is the half-cut round bar. With the flat facing downward, the cutter can be adjusted upward until it just kisses the center point. Regarding the four-jaw chuck comment, a compromise could be a free-standing bar with a cut at the appropriate height, where the cutter could extend into and be raised until it contacts it. Either approach seems better than raising the cutter until it appears to be of equal height to the top of something, but that's just me. Thanks for all the suggestions!
 
Ended up making myself this tool. Made it dual function, having the cut on opposite sides a mirror image of each other, such that the tool can be adjusted up or down. The latter may be of little use, but it seemed worth doing at the time.
 

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Ended up making this, my very first tool made on the new-to-me Webb/Takisawa lathe, and has both an upper and lower flat so that the tool can be adjusted either way. Staked a magnet into the bottom just for good measure. While aluminum or brass would have avoided chips around the magnet, I wanted the harder material since it'll be rubbing up against cutters.
 

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Starrett Planer gauge set to exactly 7.5" leaves no nub when facing. Easy peasy.
 
I made two units. One sits directly on the xslide for short cutters. The other has a bridge that sits anywhere along the flat ways for setting longer
cutters like boring bars. The units are adjustable and have rare earth magnets press fitted into the ends. These things are real time savers.
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Ended up making myself this tool. Made it dual function, having the cut on opposite sides a mirror image of each other, such that the tool can be adjusted up or down. The latter may be of little use, but it seemed worth doing at the time.
Very nice design! Looks like you prefer the "slide the gauge over the cutter and look for interference" method. I myself would prefer to hold the gauge against the tool and feel for a height difference with my fingertip. This will work in both the "tool high" and "tool low" conditions. I've read that you can feel a step as small as .001", maybe a bit less.

Your gauge could also be used to check upside-down parting tools on the back of the cross slide, if you decide to make such a mount.
 
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