I really like your idea with the two pipes in the ground so you can pivot the main pole down. Mine is a piece of concreted in PVC in the ground and I lift the pole and drop it down in that PVC. It works fine for the weight of the aluminum pole, but is a bit of a challenge with the two pipes.
Just to be clear, my main pole is 2" aluminum and does fine until winds are up around 45-50 with a flag, then it's bending pretty good and will buckle. The 1-1/4" sch40 is now inside the aluminum just to add strength. (1-1/4" sch40 is the ID, so the OD is about 1-3/4 and fits pretty snug inside the 2" aluminum sections) I previously had 1" sch40, with a joint mid way up, so this is 1/4" larger, and now a single piece with no joints. So in theory, it definitely increased strength from what I had but I'm sure it's still not the greatest.
In the meantime, I will be looking for some pipe like you used. If this doesn't hold up, i'll have a piece ready to use to make it stronger. I definitely do like your ideal though.
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