Law,
I checked my logs and I would allow 60 to 70 underway hours from the San Juans to Ketchikan. It will take 20 to 25 hours( 5 days) to get to Port Hardy(north end of Vancouver Island) and 40 to 45 hours(7 days) from there to Ketchikan. This is motor hours and includes entering and leaving harbors. Some days your travel time will be controlled by the tides or current pass slack times.
I would allow 14 days for the trip to Ketchikan. This will cover you if you need to lay over for weather or fatigue.
Don't go on a tight schedule. Take it one day at a time. Don't leave port in bad weather, wait for a better weather window. Many boaters get in trouble leaving port in bad weather because they are on a schedule or have to get back to work. Remember, its the weather that decides whether to stay or go. Don't try to make too many miles in one day. In my experience, six hours will get you 60 to 75 miles.
Plan your fuel stops and verify as best you can that your planned stops actually have gas. We experienced a shortage two summers on the central BC coast when the fuel barge either didn't arrive or had sold too much gas along the way.
Have fun, it's a great trip.
