I never said don't use that Dubro hardware. I'm saying that if you use it in the way I described, you're exposed to elevator degradation. Also, let me address the hardwood mounting underlayment. If one is using wood screws to hold a control horn to the surface, hardwood should be present (or soak with CA, as AA5 said). But many control horns come with both the horn, AND a backing plate. These work fine with balsa underneath, but I'd sure limit that to small/medium sized planes. HOWEVER, I think it's important to point out that with the Dubro #913, using hardwood underneath won't keep that pivoting from happening as I described, especially if the control surface's thru hole is a little oversize. Many people wouldn't size the thru hole all that carefully. So there will be some slop in the hole, resulting in enough clearance to allow that slippage. Sure, a tight fit hole in hardwood would be better, and would limit the screw's side play, but I think people would have to be aware of this issue beforehand. Otherwise, it wouldn't occur to people to size the hole so tight.