I've been meaning to make these samples for ages, I had to change the router bit on the dovetail jointing machine (Hoffmann) today for the big neoclassical frame moulding. There are 3 sizes of router bit and the keys are made from plastic, although the middle size also has some keys available in oak, beech, ash, and aluminium which can be used for some decorative effects.
Usually the key is only seen from the back, but with these I routed the dovetail all the way through the moulding, from the top we have:
ash frame, oak key, with liming wax
oak frame, aluminium key, with black wax
oak frame, ash key, with Harrell's antique wax
oak frame, beech key, with finishing oil
