Pair of 3 1/2" ID Commercial Garage Door Torsion Springs

When Ordering we will need: Spring ID / Wire Size / Spring length / shaft size
** Lead times may vary depending Stock and spring type stocked materials **
Follow our instructions below to confirm the correct size
For use with medium duty commercial garage doors
Black coated, corrosion resistant
Oil tempered

1. Measure Torsion Spring Wire Size

The best way to measure the wire size is to measure 10 coils and then measure 20 coils and compare the measurements to the chart below. Measure to the nearest 1/16" of an inch. It is important to make sure there are no gaps between the coils. Measuring coils that have gaps will give incorrect measurements. Gaps are more common on smaller wire sizes where the cone spreads the coils. Do not use a micrometer as each coil will not be exact.

2. Measure Torsion Spring Inside Diameter

For broken torsion springs measure the inside diameter of the spring. If the torsion spring is in one piece measure the outside diameter then subtract the wire size times two. Typical residential springs have a 1 3/4" or 2" inside diameter. Raynor garage doors may have 2 1/4" inside diameter. If the torsion spring is still under tension the ladder will not be possible. Look at the cones on each end of the torsion spring. There will be numbers like 175, 200 or 225. This will tell you the torsion springs inside diameter.

3. Measure Torsion Spring Length

If the torsion spring is broken measure both pieces and add the measurements together. If the torsion spring is still under tension it will be longer. Exercise caution when measuring a torsion spring that is still under tension to avoid injury. To get the correct length for a torsion spring under tension subtract one coil for each foot of height of your garage door then measure the remaining coils. Do not include cones in the measurement.

4. Wind of Torsion Spring

If the garage door has two springs, we highly recommend replacing both at once. Right hand wind(RHW) torsion springs typically go on the left side of the garage door and left hand wind(LHW) torsion springs typically go on the right side of the garage door. Your point of view should be standing inside the garage door looking out. Always check the wind of the torsion spring.

10 Coil Length	20 Coil Length	Wire Size
1 1/4"	2 1/2"	0.125
1 3/8"	2 3/4"	0.135
1 7/16"	2 7/8"	0.142
1 1/2"	3"	0.1483
1 9/16"	3 1/8"	0.1562
1 5/8"	3 1/4"	0.162
1 11/16"	3 3/8"	0.170
1 3/4"	3 1/2"	0.177
1 7/8"	3 3/4"	0.1875
1 15/16"	3 7/8"	0.192
2 1/16"	4 1/8"	.207
2 3/16"	4 3/8"	0.2187
2 1/4"	4 1/2"	0.2253
2 5/16"	4 5/8"	0.2343
2 7/16"	4 7/8"	0.2437
2 1/2"	5"	0.250
2 5/8"	5 1/4"	0.2625
2 3/4"	5 1/2"	0.273
2 13/16"	5 5/8"	0.283
2 7/8"	5 3/4"	0.289
2 15/16"	5 7/8"	0.295
3 1/16"	6 1/8"	0.3065
3 1/8"	6 1/4"	0.3125
3 3/16"	6 3/8"	0.3195
3 5/16"	6 5/8"	0.331
3 7/16"	6 7/8"	0.3437
3 5/8"	7 1/4"	0.3625
3 3/4"	7 1/2"	0.375
3 15/16"	7 7/8"	0.3938
4 1/16"	8 1/8"	0.4062
4 7/32"	8 7/16"	0.4218
4 5/16"	8 5/8"	0.4305
4 3/8"	8 3/4"	0.4375
4 17/32"	9 1/16"	0.4531
4 5/8"	9 1/4"	0.4615
4 11/16"	9 3/8"	0.4687
4 7/8"	9 3/4"	0.490
5"	10"	0.500
5 5/16"	10 5/8"	0.5312
5 5/8"	11 1/4"	0.5625