Hi,
I drilled 14x19mm holes in my 4" thick bench yesterday using my 36volt cordless drill, I measured and marked then I punched a point to take the 19mm auger bit while I aligned it using 2 small squares, once I got an inch in I removed the squares and carried on straight through. I re-drilled the holes using a 20mm blacksmiths drill to slightly enlarge them to give the various dogs and holders a bit of clearance, it was harder drilling the small clearance hole than the first 19mm hole. My Bench is some sort of African Hardword that is extremely dense and heavy and because of this I have put off drilling the holes for years, making do one way or another but yesterday I decided to bite the bullet and try it and it has worked out a treat. I must say that drilling the first hole was nerve wracking for fear of messing it up but afterwards as usual I wished I had done it years ago.
regards
Rustynuts.