The reality Tv mechanic posted a photo of his mangled digit on his Instagram.com blog on Tuesday (21May13), but he didn't appear to be too concerned about the injury.
In the accompanying caption, he wrote, "Doesn't look like this little dude's gonna make it, Nice know'n (sic) you little buddy."
James has since revealed he suffered the injury while using a mechanical saw at his Dallas, Texas garage - but he barely noticed.
Calling in to U.S. news show TMZ Live while waiting at his local hospital, he explains, "I was working in the shop today and my glove got caught into one of the machines and just smashed it, took my finger off. I didn't even know my finger had got cut off until I got five steps away and I was like, 'Oh man, I think my finger got cut off.'
"My wife (drag racer Alexis DeJoria) and I were on the floor looking around for the piece of finger so we could put it on ice and haul a** (hurry) to the hospital."
Despite their best efforts, the detached part of the finger was not salvageable and James is now set to undergo surgery to seal the wound.
He adds, "They (doctors) said it's gone. They're gonna take a skin graft off the chunk of finger and just sew it back on (the injured stump)..."
But James insists he's feeling fine - and has even turned down medication to numb the pain before his operation: "They're totally trying to give me morphine but I'm like, 'No, I'm fine, I'm cool, I'm all right. I'll just take the pain'. I'm fine... It's not that bad, dude."