We use a STIHL MS 250 electric chain saw. There are many choices; you don't have to have an electric chain saw. Any chain saw with a minimum 18" bar that will cut a quarter inch slot will work. For us, it just doesn't pay to use anything but electric -- no mixing gas and oil -- and no fumes created when working indoors. How many times do you have to pull on a cord to start the gasoline engine? If you have a choice and are in the market for a chainsaw, by all means buy electric.
If you can find a "skip tooth" chain, that is a better choice because it cuts better into end grain when cutting slots. STIHL stocks them in a bubble pack off the shelf at the local STIHL dealer.
Some of the smaller electric chainsaws, like Makita, are an excellent choice if you are using the T-REX Rotary Table and the Chainsaw Guide, but they will not cut a quarter inch slot. Makita is a very fast and well made saw; we use both saws and leave them set up. This is the most efficient way for us to work when we cut frames.
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