On Thu, 12 Feb 2009 18:14:45 -0600, "HeyBub"
wrote:

LouB wrote:

Or the attachment point.


Large Thanks to you and Hank for the effort. Will report back when I
solve the problem. What is "the attachment point"?


It may have another name. It's where and how the door attaches to the
opening mechanism. The opener may not know the door is all the way down and
keeps pushing. Maybe you can adjust the attachment point such that the
opener stops when the door is, oh, 1/2" from the full travel. That is, the
opener has gone as far as it can go and stops, rather than stopping when it
meets resistance.

That's what limit switches do. Not load limit, but physical travel.
You can adjust a limit switch to stop an inch from the floor, 6
inches, or 1/8". Or you can set it so it tries to lift the garage or
lower the driveway - in which case the overload switch shuts it off,
or more likely reverses it. If the limit is too low it will try to
tear the drive track off the wall.