(Youtube link at the end)
I made a couple of cutting boards with inset curves/waves.
You start with a cutting board “blank”. I know, it’s tempting to just round the corners and apply finish and be done — you’d have a perfectly good cutting board, eh? — but this is starting point for this project.
You then need to make a curved pattern, something like this. The shape of the curve is of course totally up to you. Just be sure it is a fair curve — ie: no bumps or jiggles. It needs to be smooth and flowing!
In your router you need a guide collar and a good straight bit. The thickness of the bit matches the thickness of your inset curve. I used a 3/8” bit to remove material, so I will be inserting a 3/8” strip of curved wood. Well, actually several strips that add up to 3/8”.
You can’t just cut a curve in the board and insert wood, as it will look wrong, as you’ll be spreading apart the boards that make up the cutting board and they won’t appear straight any more.
You cut the curve about halfway through the board, and then take it to the bandsaw and cut the two pieces apart. Then you take it over to the router table. You then run the bearing along the clean cut you made previously, which cleans up the rough part left from the bandsaw. The result is a clean smooth curve that perfectly matches your pattern.
Next it is time to cut some thin strips of wood for the insert
Next is the TB-III glue and clamping. Make every effort to keep the two sides of the cutting board FLAT with respect to each other. Oh yeah, and if you have them, quick-grip clamps really help here, as the pistol-grip squeezing action really helps with closing up the wide gap
After it is dried, you plane down the excess from the strip, and then I send it through my planer for a very light pass to true up both sides.