OK, I've done this enough without documenting it ... We first figured this out in 1998 by more or less copying a client's table that had a mechanism that worked pretty well ... We've built tables with it probably 4 or 5 times since then, but never carefully documented the process with notes and drawings ... I'm going to give it a whirl here ... Click the pictures to enlarge them and I hope you can figure it out .... Be sure to make a small mockup in ply or mdf to try it all out before you attempt it on your real table ... Works OK with four legs or a trestle ... We always put some felt on the bottom of the table top where the leaf closes ... strips or larger pieces .. I put a very short video of the mechanism in operation on you tube here
cad drawing of the pull out supports .. It'll all make sense once you mock it up ...
The finished table
PartsClose up of the steel apron detailOne of the four legged versions in recycled chestnut
My original coffee table drawing from 1998