I have cut several single point threads on my enco 13x40 successfully in the past. Including metric. For some reason, as i cut 1.5 mm pitch threads now, I get a good scratch pass and then on 2nd or 3rd pass, I'll get a thread cut between the previous pass. At first I thought it was me, still may be. I have slowed it down to make sure I close the half nut on the exact same spot. I disassembled the thread counter to make sure the gear was not slipping. I checked the lathe gears and have correct gears and they are keyed. I'm really frustrated at the point as I have wrecked three attempts at making a part and then numerous attempts on samples. Any ideas what might be happening?