If you thought the guy was a bum, you got tricked by his looks. Partially, he looks like that to trick his enemies into relaxing but he's also a gambler, so any money he makes is wasted. There's no clue as to why he's interested in sewing.
Jack carries a long barreled revolver that's mostly used for testing the clothes' strength, when the sewing is done. He also wears an invulernable jacket, but it's much stronger than Orion's and he won't let him have a pair.
