How to cut a circular table
Well, come to find out, cutting a circle for a table or any other project is easier that I thought! I had a customer who was wanting a circular table, which I had never done before, so I had to get creative. If you already have a router, then the whole process is relatively simple. The first thing that you have to do is get your table top or piece of wood prepped. For this project, I used edge glued pine boards to create the table surface. Clearly you can't clamp a circle very easily, so you will need to create a square surface to start with.
Once your surface is prepped and ready to go, you will need to alter your router a bit. You will want to remove the black base plate (pictured below) by removing the three screws. You may need to get some longer screws depending on the thickness of the material that you are using for the circle guide.
Remove the three screws from your router plunge base and the black faceplate should come free. Now you're ready to attach the circle guide! Now the circle guide is simply a flat board that keeps the router in a circular path. Place the router on one end of the board and mark the three holes from the top of the plunge base. Drill a pilot hole through these marks, then countersink the holes from the opposite side of the board. Using the faceplate screws, attach this board to the plunge base. Again, you may need to purchase longer faceplate screws in order to match the width of your circle guide board material. Once the router is attached to the circle guide, plunge the router bit down through the circle guide board to create a hole for the router bit. You should have a nice, clean hole in the circle guide to help reduce tear out from the bit when routing. Now, drill a hole in the opposite end of the board. The distance between the hole in the end of the board and the edge of the router bit should be equal to the radius of the circle you are trying to create. Drill a screw into the very center of the circle guide and table top and now you're ready to go! Plunge the bit about 1/4" and make your initial pass around the table top.
You should be able to see a very clear path around the table after your initial pass. I used a jigsaw to cut off all the excess material. This takes some of the strain off the router and allows the bit to travel more smoothly around the circular top.
Now you can make the subsequent passes around the table top to remove any excess material in the cut path. Just plunge the router bit a little further down during each pass around until all the material is cleared away leaving a nice circular top.
Now comes the tedious part of filling holes and sanding! I like to use a roundover bit or chamfer bit on the table top to ease the edge just a bit. Sharp edges are definitely not comfortable on the forearms! Once this prepping process is done, you can stain and finish the top. You should be able to have a product that you can be proud of!