Cutting an even triangular prism out of an organic shape

[urbansterling.co]

Hi!

The title is a little confusing. Basically, I’m attempting to make a triangle signet with a triangle cutout in the face that has sort of an organic bottom. It’ll make much more sense when you see the file. My issue is that when I boolean union my organic triangle shape, the cutout is quite uneven and rounded. I was wondering if anyone knew how to make it into a perfect triangle cutout at the top, but still organic on the bottom.
Thanks in advance

Example.3dm (7.3 MB)

[Tom_P]

Dear @urbansterling.co

one simple and fast apporach would be to design the desired edge / curve (green)
do an offset (red)
trim in top view
build a _blendSrf with position on the green and tangent / curvature on the red / trimmed edge
(blue)

does this help ?

kind regards -tom

Example_blendSrf.3dm (5.0 MB)

[urbansterling.co]

That’s super helpful, thank you very much!