Nah
Set all your tools to zero on the machine table.
This way you won't have to over change a tool setting unless you change-out that tool.
Measure the height from the table (tool Zero) to the zero surface of the part being machined.
Enter this in your fixture offset table under z. Being that you are above the tool setting plane the value will be positive.
Remember to call the H(tool #) in your program with the first Z move after every tool change.
You can cut 5 different parts with different part Zeros as long as you use (and call) the correct off-sets.
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