[Maya -> Unity] How to hide bone immediately (in motion)

Unity Engine
,
1

*I’m programmer.

My team’s director wanted to hide some bone of a 3d character immediately in specific motion.
So 3D modeler set (below) animation keys in Maya.

  • Frame 400 (30fps): bone_A’s scale x,y,z = 1
  • Frame 401 (30fps): bone_A’s scale x,y,z = 0
    [Problem]
    After imported to Unity (as fbx & Application.targetFrameRate = 30), when the specific motion run to specific (above) frame, bone_A slowly shrink from 1->0 (about 3~4 frames).

I think the reason is that Maya = Frame Base / Unity = Time Base…
I tried many ways to solve the problem but couldn’t. (Also tried to forced the scale value of that bone in LateUpdate).

Then, I find some video on youtube that shown how to set visibility of a mesh in animation key in Maya.
So, I send it to 3D modeler. But the 3D modeler said, “A mesh can’t export as motion”…
orz

Anybody here known how to solve this problem??
(e.g. Bone visibility animation key in Maya that can export as motion)

Thank you.

2

Have you solved this problem?
I have the same problem so far , and I have no idea how to do.