There's no seem tracking. It's all blind and up to the programmer to make it work. The fit up on the parts is usually pretty good. I welded about a hundred of them before they moved over to the robots. If I was the customer, I'd be pissed. I know the ones I welded were pretty friggin good, and if I saw even the "good" robot ones, I'd be really cheesed off since that's not what I was sold on when I signed the contract. 🙄