It didn't take me long to discover that I like self-feeding bits for drilling through studs and plates for my vent and drain lines. I have a medium duty 1/2" Dewalt right angle drill (DW120K, I couldn't justify buying a Hawg).

What advice can you all offer me for drilling the hole to accomodate the 3-inch ABS (main drain and vent) that I am putting into my remodel? Hole saws seem to be too shallow to go through double plates...what does anybody recomend?

Also, I'm using a 2 9/16ths for the 2-inch ABS and a 2 1/8th for the 1.5"

What is correct hole size for the 3 inch?
What about for for 4 inch?

Thanks in advance,