I am looking to smoke ribs the 3-2-1 method. It seems as though chips in the CIB stop smoking after 40mins or so so I'm curious how I would keep the smoke going with only one box? Would I add the chips after the 40mins, 20mins before they're done? i use to do the pouch method and would always add another pouch after 30 mins or so. That way the next batch of wood could start smoking before the first ran out. But with one box I'm sort of puzzled.