How to Properly Measure a Garage Door Torsion Spring
STEP 1:Determine Wind Direction
Look at the end of the spring to determine the wind direction. If the end of the spring points in the clockwise direction it is a left wound spring. If the end of the spring points in the counter-clockwise direction it is a right wound spring.
Left Wind Right Wind
STEP 2: Measure Inside Diameter
Measure the inside diameter of your spring with a tape measure or caliper.Most common inside diameters are 2”, 2 5/8”, 3 3/4" and 6
Step 3:Determine Wire Size
WIRE SIZE: A spring's wire size can be determined by several different tools or techniques. Use of a caliper, micrometer, or wire gauge are common ways to determine a spring's wire size. If none of these tools are available, you can easily measure how many coils are in 20 inches then divide the amount of coils into 20. (Example:20 ÷ 80 = .250) or simply measure ten coils of wire to the nearest 1/16th of an inch, and refer to the spring chart below.Important:the spring must be tightly compressed with no gaps with no tension. It's also a good idea to measure twenty coils as a double check.
Length of 10 Coils
Length of 20 Coils
Wire Size
1 1/4"
2 1/2"
.125
1 3/8”
2 3/4"
.135
1 7/16”
2 7/8”
.142
1 1/2"
3”
.1483
1 9/16”
3 1/8”
.1562
1 5/8”
3 1/4"
.162
1 11/16”
3 3/8”
.170
1 3/4"
3 1/2"
.177
1 7/8”
3 3/4"
.1875
1 15/16”
3 7/8”
.192
2 1/16”
4 1/8”
.207
2 3/16”
4 3/8”
.2187
2 1/4"
4 1/2"
.2253
2 5/16”
4 5/8”
.2343
2 7/16”
4 7/8”
.2437
2 1/2"
5”
.250
2 5/8”
5 1/4"
.2625
2 3/4"
5 1/2"
.273
2 13/16”
5 5/8”
.283
2 7/8”
5 3/4"
.289
2 15/16”
5 7/8”
.295
3 1/16”
6 1/8”
.3065
3 1/8”
6 1/4"
.3125
3 3/16”
6 3/8”
.3195
3 5/16”
6 5/8”
.331
3 7/16”
6 7/8”
.3437
3 5/8”
7 1/4"
.3625
3 3/4"
7 1/2"
.375
3 15/16”
7 7/8”
.3938
4 1/16”
8 1/8”
.4062
4 7/32”
8 7/16”
.4218
4 5/16”
8 5/8”
.4305
4 3/8”
8 3/4"
.4375
4 17/32”
9 1/16”
.4531
4 5/8”
9 1/4"
.4615
4 11/16”
9 3/8”
.4687
4 7/8”
9 3/4"
.490
5”
10”
.500
5 5/16”
10 5/8”
.5312
5 5/8”
11 1/4"
.5625
6 1/4"
12 1/2"
.625
Step 4:Measure Length of Spring
Use a tape measure to measure the length of the spring to the nearest half of an inch.If the spring is broken measure both segments.Measure spring only, do not include length of winding and anchor cones.
