I never mentioned in my post that I was a carpenter to trade before I moved into locksmithing and done all my morticing by hand,but I was on a job recently fitting six 3"chubb deadlocks to internal Oak doors and the forend of the lock took up most of the width of the foredge on the door,one chisel slip and it would have cost me a fortune,so decided to invest in the mortice jig for insurance,knowing my luck I wont get a full fit for ages now,You guys probably know this trick but just in case,once you have fitted the lock body and you move on to the striker plate,wet the end of the bolt with your finger and rub coloured chalk on it, I use snooker cue chalk, close the door and throw the bolt with the key a few times and it should leave a nice imprint on the door frame where the lines up,thanks to all who contributed to this post
