I have been putting Model A’s on my TOC riders. The other day I was riding and the hub basically exploded. All of the sudden when I stopped peddling and applied back pressure to brake the cones became loose and the wheel was wobbly. After taking a close look I thought this would not have happened had there been jam nuts between the cones and the rear stays on one side and a locking nut between the brake arm and the rear stay on the other side. Here is my question. Should there be thin jam nuts to lock the cones and brake arm in place? If not what keeps the whole mess from not backing out like mine did. I found a parts list for the Model A but not an exploded diagram. Any help and expertise on the Model A Hub would grateful appreciated.