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Any tips for measuring tool diameters? Calipers will work "OK" on 2&4-flute cutters but not on odd number ones.

Also any tips for managing the diameters? I've been in the habit of setting up my tools at "spec" diameter in VisualMill not measured diameter.

I haven't looked into cutter comp on the machine yet. Now I've got an expensive bit back from sharpening and it will be a smaller diameter which will cause problems with neck pocket fit if I don't correct it.

Get a real micrometer. Calipers can be forced into slightly wrong measurements.

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"Act your age, not your shoe size" - Prince

This may seem dumb but, setup a drill pattern in say mdf or hard plastic and drill a few holes and measure them all , take the median diameter. Should get you close enough and will include any runout measured as well. Set your plunge rate low to eliminate flex at contact. One more thing if you have any elongation in the holes then your Z axis is not square to either X or Y or both depending on where the elongation occurs in relation to those axis.

Just a dumb thought. LOL!!!

MK

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I'm outside looking in, just farther from the window than most.

Thanks Chris.

Mike, I think you're right. The best way to measure an odd flute bit would be to mill a slot and measure that.

Thanks guys.

Probably.

I mill a slot in scrap and measure the width of the cut.

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Jeff Scott

A drill index would get you close if the tool being measured is in the size range of the index.

-measure:


for even flute numbers


for odd flute numbers

or cut a slot.

-use your cutter comp.

If you have plug gages the right size, or know how to use a telescoping gauge properly, then drilling holes is the way to go.

If not: machine a boss by taking two passes some set distance apart, then measure the width of what's left. Slots are harder to measure accurately, and if you can then you've got the tools to use the drilling method.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services