Most often, when I have to fit a particular bend radius, I am duplicating a pre-existing design (some 40-60 year old item that needs duplicating).
As for what's most common, I see multiples of 0.1" or 0.25", but it can be specified for the inner curve or the outer curve, so it's really no help to you. Sorry.
TC Pro Platinum 2020, 2019, 2018, 2017, 2016 & 2015 (all with LightWorks & RedSDK) & V21
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