thank you very much, Very informative.

regards

Jean-Paul
"Musky" wrote in message
...
http://www.dpindustries.com/onepiece...nterweight.htm

more on doors:

http://www.hangartrader.com/aircraft_hangar_doors.htm

Jean-Paul Roy wrote:
How can you get a 40 ft garage style door to work properly. Can you
imagine
one track holding each end. Wouldn't the midlle colapse when in the up
position?