I built the Unifence cove cutting jig shown in the link below.
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use, set the saw blade at the height of the cove to be cut. Bring the parallelogram jig (shown over the blade in the photo) to the forward and rear blade edge. Adjust the angle of the Unifence cove cutting jig to match the long side of the parallelogram. Adjust the Unifence position to hold the wood where the cove is to be cut (no angle changes required after initial setting). Set the blade at about
1/16 inch projection and start cutting the cove, adjusting the saw upward until the cove is complete. The cove roughness was easily removed in about a minute with a ROS or a gooseneck scraper. Once the angle is set, all you have to do is move the fence as you normally would to adjust for different wood widths or postions you want a cove to be cut.
I tried clamping a fence to the tablesaw to cut coves. It works, but it is no fun setting up and you have to add small wood spacers to provide a surface for the clamps to grip the bottom of the saw. You have to finess the clamp position and the jig angle. This it is not necessary with the simple jig I made.