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ergotron lx pole extension using schedule 40 pipe
Response to question: I changed it after I took this photo. The new pole is about 4 feet high off the ground. At the ground level it screws into a threaded base which is bolted onto a wooden rolling platform. The threaded base was sold with the lengths of pipe and was flat mount, 4 screws. At the top of the pipe I have an extension coupling. The extension coupling has a short ~4 extension screwed in, with a pipe cap on top of that. The width of the extension coupling is such that the ergotron slides over the ~4 extension and sits on the coupling without sliding down the pipe. The cap on top is mostly aesthetic but potentially keeps the egotron arm from sliding off the top (though if the whole thing fell down, that’s a different problem). I put a cinder block on the wooden platform as a counterweight to prevent tipping. Hope that helps.