My last couple of flights from HND have been leaving in the 4:00-4:30pm range. I usually get to the airport around 1:30-2:00pm and I'm usually in the lounge in about 20-25 minutes after I get in line at the airline counter (AA, DL, and JAL). Most of the variation is the pat down rate at the metal detector and the relatively long walk to the Delta SkyClub.