I think you missed the point, I need sphere to move WITH the hand even when I weld it to HRP.
But according to your animation, this could work and you can just tween the Y value. Your rock is huge and welding to HRP seems like the easiest and most efficient way to do this. Welding it to the hand only follows one hand movement, welding it to HRP makes it so you can adjust it according to the location of the two hands. Just have the hands touch the rock and change the animation, you see how it moves up a bit? Add that to the momentum effect and youāve got a really seamless and good looking throwing animation IMO.
You want it thrown down the middle right?
You welded sphere to body and increased C0 manually. What I am asking for is the mathematical formula of getting position between both hands since I posted this question.
I donāt get it sorry. What do you need a mathematical equation for? The title of the post is how you can weld between two parts so I assumed you just wanted to make a weld between the two hands. I donāt know the math of what you want, this is just how I would do it.
Asked in a few other helper places and it has been solved gladly. Hereās a mathematical equation for finding local position of a vector that is found from two vectors.
local MidPoint = (RightHand.Position + LeftHand.Position)/2
local C0 = HRP.CFrame:inverse() * MidPoint
w.C0 = CFrame.new(C0)
The thin black vector was the vector I aimed to find.
Thanks to everyone who checked and answered. Iām leaving this answer below if anyone gets in the same situation as me.