Cutting a circle out of wood is usually done with a jigsaw and takes a very steady hand.
The video above walks through the steps of making a round table from 2x4s.
First, determine theradiusof your table or wheel and mark that length from your saw blade on the table.
Then drill a hole through the top of your table saw using a 1/4 carbide bit.
Drop the blade all the way down on your table saw.
Place the end of the bolt through the hole you just drilled on your table.
The wood should now rotate freely around the bolt across the table saw.
Slowly raise the blade after each pass until your circle is cut.
Always wear eye protection when using a table saw!
Check out the link below for full instructions on building the table.
Heres anothervideohes produced that details cutting a circle using the same technique.
Cut a Circle with a Table Saw| GREENPOWERSCIENCE