Angle grinder chainsaw - video

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OK, you have a right angle grinder, and a spare chainsaw blade and chain, to modify this tool required way too many other game changing tools besides a hammer and screw driver. For $30 a mains AC powered chainsaw can be had from any big box store. And it's purpose built with the right gear ratios for wood cutting speeds of the chain.
Sure, home built is because either you are remote, frugal, or it's a one off, and no one makes the tool, or cost prohibited, but this is, "lets make a video" of making something you can buy that will work better if purpose designed, and not hacked from what the tool was for. Such clever humans.
What I have done, is take a 20" chainsaw blade, modify it to fit on a 9" pole saw from harbor freight, and cut big limbs off overhead branches, and run fast to live and tell.