for future reference, what i did for tight inside radii is to not cut the rib off the t- molding but rather make lots of cuts the full depth of the rib so that when you bend the t-molding, the rib fans out. im sure theres a single word to describe what i have just described but hopefully you know what i mean! then i used 5 minute epoxy in the slot and just held the t-molding in place by hand until the glue had set. the epoxy wont really stick to the t-molding as such but of course sticks amazingly well to wood and mdf. thus it will lock the rib into the slot...