What is awafer lock


The 81 service manual can be found here.
Wafer keys were used prior to the current pin and tumbler design used today. These are discontinued and are no longer available.
Information on wafer keys and keying can be found here.
To remove the knob:  Turn key 45 degrees clockwise Push in catch push pin and pull off knob  
*The older wafer style locks did not use a knob catch.  The chassis must be disassembled before the knob can be removed because it uses the wafer lock chassis spindle.
The table below provides the Ilco cross reference to the Schlage keys.  Ilco Identification Section Pins Schlage Part # SC1 C 5 35-100 C SC4 C 6 3...