If you are screwing a compression spring onto a mating part you would want the coil direction to matc h that of the threads.
Left hand coil spring.
A coil spring can be wound in either a left hand or right hand direction similar to a screw type thread.
Compression springs can be left or right hand coiled.
To determine the compression spring coil direction hold the compression spring with its axis on a horizontal plane.
The direction of wind of a spring can be determined by simply holding it in your hand with your fingers placed around the outside of the body and your thumb pointing straight up.
The fingers should be placed on the outside of the body and your thumb should point upwards.
In the us most screws are right hand.
The direction of the spring wind can be easily determined by holding it in hand.
If the last coil of the spring points in the same direction of your fingers then you are looking at the right handed spring.
If it s in the 3 o clock position the spring is right hand wound.
If the wire is jutting out at the 9 o clock.
If it can be.
Pick up your spring and look into it.
If the direction of the coil from top to bottom can be simulated by bending the index finger of the left hand the coil is left hand wound.
Pick up the spring and look into it.
For compression and extension springs.
Right hand wound rhw vs left hand wound lhw.
If the last coil ends in the same direction that your fingers are pointing that is the hand direction of wind of the spring.