Lesson group #3 arrived today! New textbook, workbook and a pinning & service kit. Glad to see the workbook in this set is more substantial. 🙂 So far I’ve spent more time waiting than actually working on the course. Enjoying it quite a lot though.

Next lesson gets deeper into lock designs and how they actually function, then after that it’s more about master keying. I like how the coursework keep circling around to re-cover topics in greater depth. Means it doesn’t matter so much if you didn’t entirely understand something the first time round.