Thanks dc42, It must be the former as swapping the steppers transfers the issue. I feared it was the Rambo, has anyone had any success with replacing the driver chips? I'm confident of getting a new chip reflowed but haven't ever tried to get a knackered chip off the board. Any tips would be greatly appreciated, else I'll use the smallest tip I've got for my heat gun and see what happens. It's useless now, what damage can I do? :D
John
John