How do you have a 'customized' standard thread?
The tap drill size for a 1/4-20 thread can vary a little based on the percentage of full thread you want to achieve, but in 98.3% of the cases using a #7 (.201) drill for the tap drill will suffice?
Since there is only 1 variable pointing to the thread files, your startup batch file for different customer settings is the best way to go. The option of writing a script to change the setting mid session would also work, if NX will pick up on the changed value.
I think what Vegetagaru is saying is to have multiple entries in your treads.dat file for the same size, but different values.
Drill callout TapDia HoleDia
Cust1-1/4-20 .250 .201
Cust2-1/4-20 .250 .199
Cust3-1/4-20 .250 .207
(rest of data columns not shown)
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