[TowerTalk] Stub mast strengthening

[GW4BLE]

I have a question concerning 'sleeving' (can't think of a better way to describe it) -  I have a 16' x 2.5" OD thick-wall aluminium tube that will be used as a stub mast, would inserting 6' x 2" OD thick-wall aluminium  tube into the bottom of the tube add to its' 'strength' in any way or would it just add unnecessary weight?
Sliding it in makes quite a snug fit, but not exactly 'tight' 

Steve
GW4BLE

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