table saw jig for scooping out chair seat

Jigs and Fixtures! If I'd have two middle names....
My woodworking is limited; there is a couple who I enjoy helping though. They have to see this. The instinct to rectify the transition from pivot motion x transverse cut would be the only focus. Probable modification might be a semicircle instead of Vee, and clear the 'pin' somewhat from the guide. That would reduce or even out the cusp between passes. That is certain to be a 12'' diameter blade; possibly larger. Tried to scale the distance between pin holes, looks to be 3/4''. Also relieve for dust at bridge uprights would re-position the panel more consistently for each pass to start and stop.