[mrstampe]

JCD wrote:

I do have a follow up q for you if you have the time -- when you use the spiral upcut, do you have to drill a starter hole to the required depth first? Or can you plunge down adequately with the spiral upcut bit? Also, what size bit do you use?

JCD

I used a 3/8" spiral upcut. No pilot hole is necessary, as this bit mimics a drill bit in its design. It was a compromise in size, having to be small enough to make a full-thickness bore in one pass and using the same bit for two shallow passes of different radii to form the lip. The 1/2" bit might have allowed one pass for the lip, but that's 33% more wood dust to throw around on the full-thickness cuts. Again, there's more than one way to skin this cat (so to speak).