"...the lack of the binder ears having any internal reinforcement"??? From Prowler quoting me.


Binder ears are the seat lug's portions that has the seat post binding bolt running through them. That these lug portions are only the lug shell with no added material inside them make for a easily collapsed/distorted shape when the binder bolt is tightened. If a too small post size in used or too much bolt torque is used the ears are crushed inwards. By adding brass/bronze to the ears' hollow insides or, better, fitting a sleeve and brazing it in place one makes the clamping faces (ears) essentially unable to crush. In the photos you can see the start of this crushing on the right ear just as it blends into the lug's body. See this image (from 1884) of a lug's ears that have been reinforced then nicely filed open. You can just barely see the line of brass between the sleeve and the lug's shell. Andy


I just added an even better view of reinforced lug ears. Still from the same era. Andy