First thing is to make sure you have the correct tool holder for the insert. There are 2 main styles. Negative and neutral (positive) style. On the negative style, if you look at your tool holder the tip will tilt at a downward angle. On a neutral, the tip will point straight out being parallel to the top of the holder. The insert for a negative the clearance angle is 90 degrees to the top. On the positive insert, you can see a clearance angle on the tip. These are one side usage only. The tool holder provides clearance. The This allows you to use both top and bottom side of the insert. Normally the holder will have a N for negative or P for positive in its part number.

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If you have the correct style, then what Bill said below applies.

Al-USA

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