I know you're only heating the lug nut, but be very careful not to apply any heat to a rim with an inflated tire, the heat can cause a tire to explode.
Watch this video staging a tire blow up and how fast it happens...
Be safe,
Mike B
Mike Boteler
1956 Chevy 3100 Resto Rod 1952 Willys M38 Army Jeep 1983 Jeep CJ7 Laredo 1984 Jeep CJ7 +++++ Silver Spring, MD