The chair had suffered from broken tennons caused by a heavily woodwormed frame support block. The very thin tennons were then not capable of taking the weight of the guest at the customers dinner party.... Picture on the left showing cutting out from the underside of the frame the place where the new tennons will be inserted. This way the work is not visible from the top. The tenon was originally only 1”. To hold the new timber, it needs to extend further into the frame to g