I need a picture of this! What I'm thinking of as how you did this would require 16' of string for an 8' door.
Help!
FD
No pics. ...and I took i down a few years ago. We had too much junk stacked in the garage to get the cars in there. I'm slowly getting to the point where I can get a single vehicle back in there (two car garage).
Mike's steps to a mobile car stop....
1. Get a tennis ball.
2. Put a nail or piece of metal through the tennis ball and make a loop on one end.
3. Figure out where you want the tennis ball to contact the vehicle windshield
4. Place a eye bolt above the point on the ceiling (affix appropriately).
5. Run a piece of string through the eye down to the tennis ball and tie it to the tennis ball.
6. Tie a washer to the string so that the tennis ball hangs at the right place.
7. Affix a second eye bolt to the top of the garage door.
8. Close the garage door
9. Tie the string to the washer (again)
10. Run the string through the eye bolt installed in step 7 and pull the tennis ball up until it almost touches the eye bolt in step 4. Tie the string off.
11. Open the garage door and watch the ball come down.
12. Close the garage door and watch the ball go up.
13. Have a beer and repeat steps 11 and 12 until you feel good (you might even pull the car in (but not with the beer close by)).
14. Show the new mobile tennis ball to SWMBFAO and watch her roll her eyes at you (but she will use it).
I hope this helps...
...and YES it will take 16-30 feet of string. Basically the distance from the windshield to the garage door.