Most importantly, you will be greeted by friendly staff and associates that will help you select the right garage door for your home. We welcome the opportunity to supply, install, and/or repair your garage door as well as answer any door questions you may have. When you choose us, you will quickly discover why thousands of Riverbend area customers from house to house and generation to generation have chosen Dan's Garage Door Service as their “DOOR KEEPER” for over 40 years.

Speed of a thrown winding bar:: The springs, being in balance with the door, effectively are able to launch a typical 150 lb door at 10.6 mph speed. An 18-inch long by 1/2-inch diameter steel winding bar happens to weigh about 1 pound. Since momentum is conserved, this 150:1 ratio in weight of the door to the winding bar means the fully-wound springs could potentially throw a winding bar at 10.6 mph * 150 = 1590 mph = 2332 ft/sec, assuming the energy were perfectly coupled and transferred. If the energy transfer were only 1/3 efficient, this would still be the 800 ft/sec speed of a typical pistol bullet. Except it is a foot-and-a-half metal spear, not a bullet.


Trading diameter for length: Observe that in the spring rate formula in the table above, factors D (diameter of coils) and N (number of coils) appear together in the denominator of the spring rate formula. Algebraically, given equal wire sizes, this means that the product of the coil diameter and overall length produces the spring torque, not the diameter or length alone. Physically, this means that you can trade off torsion spring coil diameter versus overall length in inverse proportions to maintain the same torque rate. Trade-off example: A spring with 2-inch diameter coils that is 36 inches long equals a 1.5-inch diameter spring that is 48 inches long, because the product in both cases is 72 (inches squared). This assumes that wire size is equal in the trade-off, and that you have not counted dead coils in the length. Service technicians use this principle to make quick substitutions for what's on their truck versus what you need. But if you understand this, you're ahead of many technicians who don't know this trick. Maybe now you can educate the next one you hire.
The second stage of the wireless garage door opener system solved the opening-the-neighbor's-garage-door problem. The remote controls on these systems transmitted a digital code, and the receiver in the garage responded only to that code. The codes were typically set by eight to twelve DIP switches on the receiver and transmitter, so they allowed for 28 = 256 to 212 = 4,096 different codes. As long as neighbors used different codes, they would not open each other's garage doors. The intent of these systems was to avoid interference with nearby garage doors; the systems were not designed with security in mind. Intruders were able to defeat the security of these systems and gain entry to the garage and the house. The number of codes was small enough that even an unsophisticated intruder with a compatible remote control transmitter could just start transmitting all possible codes until he found one that opened the door. More sophisticated intruders could acquire a black box master key that automatically transmitted every possible code in a short time. An even more sophisticated method is known as a replay attack. The attacker would use a code grabber, which has a receiver that captures the remote's digital code and can retransmit that digital code at a later time. The attacker with a code grabber would wait nearby for the homeowner to use his remote, capture the code, and then replay the code to open the door when the homeowner was gone. Multicode openers became unpopular in areas where security was important, but due to their ease of programming, such openers are often used to operate such things as the gates in gated apartment complexes.
Loosening or tightening the set-screws is the moment of most risk, since the end-wrench is a potential missile if you slip, and your hand is close to the cone. When the wrench is removed and only the rods are in place, it would seem that the worst that could happen is that the rod is flung out and the captive spring and cone rattle around, assuming you are keeping yourself clear of the rod's radial disk of rotation, and not leaning on the rod such as to fall into the apparatus were the rod to slip out of your grasp. The torsion shaft design has the virtue of capturing the mass of the spring and cones reliably on the shaft, preventing these parts from launching themselves as projectiles, even in an accident.

Direct Garage Doors specializes in the supply of residential and commercial garage doors. If you're interested in purchasing a new garage door for your home or business or need to replace or repair your existing garage door, we can help! We can supply you directly from a range of the best residential and commercial products in a variety of styles and colors to enhance any residential or commercial property
Charlotte, NC is  a bustling market for new homes, business construction and restoring old homes.  Charlotte’s real estate market is booming. Our company has been a part of this growth by installing and repairing over 50,000 garage doors since 2001. In this span of time, we have had no issues with the county inspections office. We have done this by making sure that our clients buy the right doors, and have permits in place, if needed. Keep in mind that we are not general contractors, so we do not supply permits, but we provide the information and resources for you to easily apply for permits if one is needed for your project.
Since 2015, we’ve tested a variety of devices such as smart locks, video doorbells, DIY home security systems, thermostats and more. We use these testing experiences to inform our evaluations of other equipment. As time and resources allow, we occasionally test new types of products, but there are still some circumstances where we’re unable to conduct in-house tests. When testing isn’t possible, we conduct thorough research using the same standards we apply to our in-house tests – this is the case with smart garage door openers. We’ve reviewed garage door openers since 2011. 

Garage Door Opener Co

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