Idiocy: A Cautionary Tale
By Josh Simons on Sep 10, 2006
I noticed the other day that one of the extension springs on one of our garage doors had broken. These are the large springs that help the electric garage door opener pull the door into its open position.
I found a great site that sells all sorts of garage door replacement parts, including extension springs. They have a page that includes instructions on how to determine which replacement springs to order.
If the existing springs aren't color-coded, one must weigh the door. To do this one must disconnect any remaining springs, disengage the electric door opener and lower the door onto a bathroom scale. The procedure detailed on the website starts with the following step:
1. Raise the door to the full position and secure. The best way to secure the door in the up position is to snap a vice grip or C clamp under both the bottom rollers.
Well, the clamps were in the basement and I was in a bit of a hurry. I disconnected the one remaining spring. And then I pulled the release lever to disengage the garage door opener. And then the door--now freed--began to slide. Slowly at first. I'm very thankful that I moved too slowly to actually attempt to get under the door and catch it, because it accelerated quickly (9.8 m/sec\^2, if I recall correctly) and closed with an impressively loud finish as it smashed into the floor of the garage. More precisely, it landed on the bathroom scale I had previously positioned for subsequent steps in the weighing procedure. This was a sturdy old steel bathroom scale. It's now in the trash--crushed and with a very noticeable dent furrowed across its surface.
After buying a new scale, I managed to carefully weigh the door and reassemble everything. I will soon place my order for the appropriate replacement parts.
I, of course, should have followed the directions. And I should have looked at the table of replacement springs more closely. It shows that garage doors weigh in the range of 60 lbs to 300 lbs.
For the curious, my garage door weighs 138.5 lbs.