Notes from the author about this project.I used 3/4" maple for this project. I used two different bits 1) Amana RC1148 60 degree vee and 2) 1/4" downcut flat 46202-K.
When designing this project I decided on 3.5" diameter coasters, however, I believe 4" is more common. When purchasing cork to glue to the bottoms I found 4" cork circles at a Michaels store. I used DAP contact cement to glue on the cork. Feel free to modify the design as needed.
I ended up resawing the thickness of the coasters on my bandsaw to 1/2". They were fine at 3/4" but I chose to make them thinner because I added cork to the bottom.