Hi David
As a framer, I am mostly self taught at yhe start. The first 15 frames or so were cut using a method of mapping and fitting. I had not heard of square rule at the beginning nor had I studied old square rule buildings. Mapping was, to me, endlessly an exercise of beating back uncertainty. I would draw up plans and know the frame cold but I could not say what the length of any piece was without surveying all the abutments. My hat is off to Mark Brandt, Mike Goldberg, Curtis Milton and Will Beemer for their presentations that opened up much needed insight into square rule and, for me, a far more clear layout of square rule.
In the early days of square rule, housings were not used, from my observation. Rather gains were cut in the non reference sides, without consideration for the joint, running past the joint horizontally and vertically. Joints most often beared on the tenon alone. The pieces all had an asymmetrical look, with an unworked ref side and gains in the non-ref side. My reasoning for housing is to provide support, restrain rotation and to hide shrinkage also to provide a more symmetrical look.
It has been a long evolving process for us all.
