Changing to a system where instead of screws thru the brass outer booms in the tub I will be using boom clamps to stop the booms from sliding. The boom clamps are 7075 T6 and all 4 weight 8.5g total with titanium 4-40 screws. Aluminium has a higher coefficient of friction than plastic, so for the same clamp pressure will hold the booms better, and also doesnt have the issue of creep that causes plastic to loosen.