[Sawman7]

Have an order for a 6 foot round table to be built from 4 large thick pieces (2 1/4 x 20'' wide)of rough cut pine, to be placed on a large 28''dia. trunk of pine,
plan to dowel and glue the pieces for the top, but would like suggestions on how to attach and support

 

[cabinetman]

Have an order for a 6 foot round table to be built from 4 large thick pieces (2 1/4 x 20'' wide)of rough cut pine, to be placed on a large 28''dia. trunk of pine,
plan to dowel and glue the pieces for the top, but would like suggestions on how to attach and support

If your mating edges are jointed for a good fit, all you need is glue and clamps...no dowels. Using cauls will maintain alignment. If you aren't edging the ends of the boards with a banding which would tie them together, movement issues would be minimized.

I would acclimate the lumber before assembly. If kiln drying is an option I would go that route. You didn't say the finished height of the table, and I'm assuming it's a dining table. You could secure a plywood plate (larger in diameter than the stump) on top of the stump, and screw up through the perimeter of that into the top boards. In doing that, you can use one of the center boards to screw in securely to the center of it, and other boards make an elongated slot for a pan head screw and washer to allow for movement issues.

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