The offset might get you close occasionally, but it's not accurate.Bhb wrote: ...
As for the Tri-Grip and the "dual angle" layout, it is established with a mere 5/16" additional movement towards the positive axis point than what you would do with a standard T grip.
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Bill Hall
The Dual Angle method produces a grip centerline for the T-Grip style.
That line passes through the center of the thumb, and splits the bridge.
The Tri-Grip starts with the middle finger centerline which doesn't pass through the thumb, and doesn't split the bridge. Therefore those two lines are at an angle to each other.
How much of an angle is based on the offset to the thumb centerline, finger spans, finger hole sizes, and bridge size.
Since the angle is variable, based on each hand, there can't be a simple offset to the pin location.
I'm working the math to take the parameters used in the Tri-Grip, and computing the equivalent T-Grip specs.