I've been glaze firing to cone 6 with a 17 minute hold at the highest temp. I have been turning of the vent (of my Skutt with KilnMaster) after the 17 min hold. Should I leave the vent on until it cools down to 100 degrees? I was thinking that by turning of the vent it would slow down the cooling. I like my results, but it takes SO long to cool down with out the vent on. Thanks for your help!!