Player's right hand doesn't rotate?

I'm trying to get the right hand to rotate, but it doesn't rotate. What am I doing wrong?

CharacterSetup.OnServerEvent:Connect(function(player)

    local Ball = game.ServerStorage.Ball:Clone()

    Ball.Parent = player.Character

    local Weld = Instance.new("Weld", Ball) 

    Ball.Size = Vector3.new(0.6, 0.6, 0.6)


    player.Character.RightHand.Rotation = Vector3.new(90, 0, 0) --this part here


    Weld.Part0 = Ball

    Weld.Part1 = player.Character.RightHand

    Weld.C0 = CFrame.new(0, 0.4, 0)




end)

Thanks!