Skeletal mesh collision changes during runtime

is there a way to change the collision response of specific bones during runtime ?
I’ve got a hand mesh that I want to disable the fingers’ collision on specific events : used in VR, the hand has collision enabled to hit physics objects, grab them, but when I release the actors, the fingers collision send them away (the hand opens, the fingers deploy and the object that was attached is thrown away in the sky).
I want to disable the finger collisions when grabbing, and reactivate it some delay after releasing an object.

I found this topic : Enable physics for specific bones - World Creation - Unreal Engine Forums but didn’t help, i’m working in BP and can’t find out where to set the bone type.