Are Motor6Ds the best way to do this?

So i want to place the arm in a fixed position and rotation while still being connected to the body. I tried using Motor6Ds (script below) but the animation for the arm still plays and the arm moves. I dont want it to move. Could i change something? or are Motor6Ds not a good way to do it?

script.Parent.Equipped:connect(function()
	if script.Parent.Parent:FindFirstChild("Humanoid") then
		local tool = script.Parent
		local char = tool.Parent
		local LeftShoulder = char.Torso["Left Shoulder"]
        LeftShoulder.C0 = LeftShoulder.C0 * CFrame.Angles(math.rad(0),math.rad(-30),math.rad(-90))
	end
end)

Motor6Ds allow movement. you should try using Welds.

http://wiki.roblox.com/index.php?title=Weld