Sorry that your Thread had gotten missed, sadly it does happen from time to time. With my Post, it will bump your Thread back-up on the Board and one of our Mac Pros will chime in!
If you are just starting, commonly beginning with white pine trim wood bits that provide less resistants to your Mac chewing it. As the joy of chewing increases, the size of the bits increase as does the strength of the provided wood, as they commonly move to white pine construction lumber.
Assure that you never provide treated lumber as it is poisonous!