I have a vague recollection that he lost his shirt at some point, possibly building rockets. Possibly there was something in Masters of Doom[1]? I don't have it

I have a vague recollection that he lost his shirt at some point, possibly building rockets. Possibly there was something in Masters of Doom[1]? I don't have it near me, so can't check. 1: Biography of id software, obviously heavily featuring Carmack. Highly recommended.