I often find the when generating a die (that might need an exact fit, that the reality of the folded dimensions don't always meet the expectation.
So I am assuming here that any dimensions we put in are either external dimensions or dimensions to the centre of the fold.
Other generators I've used allow an option to select Internal or External dimensions.
Therefore by selecting Internal dimensions, the software will automatically adjust the dieline to suit the material thickness and ensure that when folded, the internal dimensions are correct.
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