10-06-2018, 06:02 AM
I've had to do this before and usually try to attach a piece of plywood so the pilot drill can get a bite for the hole saw to start.
This looks like a good solution, use a hole saw the same size as the existing hole as a guide with the larger hole saw mounted above it:
This looks like a good solution, use a hole saw the same size as the existing hole as a guide with the larger hole saw mounted above it: