This is like a huge radial arm or chop saw. We use it to cross cut sheets of plywood. The saw is a standard circular saw mounted on tracks
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The tracks are mounted on our homemade frame. Along the bottom, you can see a lip to hold the plywood in place.
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 Here's a stage weight. It counters the weight of the saw. Thus, making it easy to lift the saw back to it's home position.The tracks and saw holder comes in a kit. The kit runs around $200. We purchased the MDF and used scraps for the misc. parts.  bbbbb3.jpg