Right-hand versus left-hand winding: Springs are chiral, that is, wound or "laid" in either a left- or right-hand orientation. This is a critical property of their design and specification; you cannot substitute a left for a right or vice versa. If you were to grasp the spring in your hand, and if your right hand orients the tips of your fingers like the ends of the coiled wire when your thumb points "out" of the core of the spring, then you have a right-hand spring; likewise left (which end you grasp does not matter). (This also happens to match the "right hand rule" of magnetic polarity, if you happen to be knowledgeable in such esoteric subjects.) Another way to identify the winding is to examine the spring vertically in front of you; if the coils facing you rise going to the right, it is right-hand (thus you can remember, "rise to the right is right-hand"), and likewise left indicates left-hand. Another way is to view the coil axially; a right-hand spring winds in a clockwise direction as it recedes away, and a left-hand spring counter-clockwise. Yet another way, not so easy to remember, is to hold the spring vertically and compare the coil shape to the letter "Z" (indicates right-hand lay) or the letter "S" (indicates left-hand lay).
Extension spring systems should always be restrained by a safety cable that runs through the middle of the spring, tying off to a solid point at the rear and front of the horizontal door track. Extension springs represent a hazard to bystanders when a spring, pulley, or cable breaks under tension. Metal parts from extension spring systems can suddenly be launched.
Our value pick is the Chamberlain PD76EV. It costs about $50 less than our top pick, but it has most of the higher-priced model’s advantages. The PD76EV has the same lift capacity, horsepower, lift system and automation compatibility. However, it doesn’t come with advanced features such as a backup power source, close timer and keyless entry pad. If you can live without those, this opener is a great choice.

Trading wire size for length, diameter, or cycle life: Now we are really going to save you some money, if you just recall your high school algebra class (and I don't mean that cute cheerleader who sat next to you). If you further understand the role of the 4th power of the spring wire size (letter d in the formulas above) in the numerator of the spring rate formula, and how to increase or decrease d to compensate for changes in length, diameter, and cycle life, then you're qualified for elite spring calculations. Matching springs is a matter of equating the 4th power of the proportion in wire size change to the proportion of change in the diameter or length or the product of both diameter and length. However, it is usually best to only increase wire size when substituting a spring, since this does not derate the cycle life. If you observe that the formula for bending stress is proportionate to the inverse 3rd power of the diameter, then physically a proportionate increase in wire size will result in a dramatic increase in cycle life of the 3rd power of that proportion. Trade-off example: Yawn with me while we ponder my original spring once more. Let's say I was in a fit of engineering mania, and wanted to replace my spring having a 0.2253 inch diameter wire (d = 0.2253) with a 0.262 wire version (d = 0.262). How much longer is the spring with equal torque rate, assuming we use the same coil diameter? The proportion of this change is 0.262/0.2253 = 1.163, and the 4th power of that is 1.83. This means the length must increase by a factor of 1.83 (again, not counting dead coils). Recalling that the length in Example 1 was 102 non-dead coils, the heavier wire spring must be about 1.83*102 = 187 coils, which when adding 5 dead coils and multiplying by the wire size to get the overall length, is (187+5)*0.262 = 50 inches, versus 24 inches in the original. So using this heavier wire more than doubles the length (and thus the mass and thus the cost). While the cost about doubles, the stress goes down by the inverse 3rd power of the wire size proportion, or 1/(1.163**3) = 0.64. Sress is favorably, non-linearly related to cycle lifetime (halving the stress more than doubles the lifetime), so this decreased stress should more than double the expected lifetime of the spring. While the up-front cost is more, the true cost of an amortized lifetime is much less. In short, per cycle it is cheaper. Ah, the wonders of engineering calculations! Conclusion: Observe that the stress formula (and thus the cycle lifetime) depends only on wire diameter (d) for equal torques. Thus the only way to improve cycle lifetime is to use heavier wire. For equal torques, heavier wire size, due to the exponents in the formulas, increases cycle lifetime much faster than it increases mass (and thus cost), physically speaking.
Make sure the door is balanced. Close the door and pull the emergency release cord (always close the door first so it can’t come crashing down!). Lift the door about halfway up and let go. The door shouldn’t move. If it slides up or down, the torsion spring needs to be adjusted (or maybe even replaced). Adjusting the torsion spring is dangerous, so don’t attempt it yourself (you could get seriously hurt). Call a pro to adjust it.
In 1921, C.G Johnson invented the upward-acting garage door and revolutionized the way the world entered their homes. For more than 97 years, Overhead Door™ garage doors have been securing and providing families access to their homes. Overhead Door™ garage doors are assembled in the United States and sold at over 450 authorized Ribbon Distributors throughout North America. The Overhead Door™ brand and Overhead Door™ distributors are synonymous with quality and dependability. To ensure you are getting the genuine, the original, make sure to always look for the Red Ribbon.
The German-made, .75-horsepower (equivalent) Direct Drive 1042V004 garage door opener doesn't use a belt drive or a chain drive. Instead, the mobile motor crawls along a stationary chain, making it exceptionally quiet. This garage door opener is also feature-packed, though the wireless entry keypad is an extra-cost accessory. Reliability is excellent, and installation is at least a little easier than some other garage door openers. This opener is also sold under the Sommer brand and with different model numbers, but all are similar.
And for some extra features, you'll appreciate accessing the system through the MyQ smartphone app. You can set up this Chamberlain opener to automatically close the door after 1, 5, or 10 minutes, which is great for people who are a bit forgetful. We also really like the motion-detecting control panel, which turns on lights whenever it records nearby movement.

Garage Door Repair

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