David Martel wrote:
Joseph,

I think that the OP meant that they are 8' poles with 2' buried and 6'
above grade. It's not clear why he can't pull these poles and use longer
ones. I agree that extending the above grade height of the poles without
burying them deeper may be a problem. It might help to know how much he
wants to extend the poles above grade.
Assuming he knows what he is doing, I bet several feet of pole with an
outer diameter slightly less then the inner diameter of the existing pole
could be epoxied in to connect the pole with it's extension. Welding might
be a better solution than epoxy.

Using the smaller diameter as a connection pin would also be possible.
One could drill and pin them for permanent connection if welder isn't
available.

Depending on what they're supporting and how much extension is needed,
wind loads could become an issue. Just noticed the other day the right
foul line fence at one of the local little league fields was laying
flat. Standard chain link w/ the green plastic privacy barrier on it --
that happens here about once every couple of years. Yesterday the city
had set new posts --

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