Like two ballroom dancers, unless both partners work together with flawless grace, the whole dance falls apart.
Following the analogy one step further, sewing machine timing may actually be more like a square dance. There are hundreds of individual parts all moving, turning, and operating all at the same time. Unless they synchronize their performances, the sewing machine fails to work. Two basic areas are concerned.
Initially, we see the synchronization of the needle with the hook. Together they move, dancing around one another. The hook wraps the needle thread around and dances off forming a stitch in time. Sewing machine technicians describe this timing relationship as hook-needle timing.
Next, the graceful motion of the feed dogs rises, glides back, drops, and rises forward in perfect harmony with the needle as she rises up and plunges below the needle plate. This is known as feed dog timing.
Indeed, just like an elaborate dance, the timing and coordination feed dogs, needle, and hook systems must work together in harmony. Even very small irregularities will distort or even halt the sewing process. Sewing machine timing is critical and must be adjusted and maintained in precise synchronization at all times.
To understand the timing of the feed dogs and needle, we can simply remove the presser foot and rotate the hand wheel forward. As it turns watch what happens. The needle moves from it highest point down toward the needle plate. The feed dogs reach their farthest point toward the back of the sewing machine. The feed dogs drop under the needle plate just before the needle point reaches the needle plate. The needle continues to move down dragging the upper thread under the needle plate, and proceeds toward its lowest point.
To understand the relationship between the hook and the needle, you will need to remove the needle plate and front cover. As the needle reaches the bottom of its swing and begins its rise back up; a loop of thread forms along the back of the needle. A special cut out on the back of the needle to accommodate this loop is called the scarf. The sewing machine hook slides behind the needle. The point of the hook slides into the thread loop and pulls the thread around the bobbin.
If you watch very carefully, you can see how the upper thread is drawn around the bobbin thread and then pulled tighter and tighter as the needle continues rising. When tensions are properly set, the two thread form a locked stitch inside the fabric. This same process continues stitch after stitch. Both the feed dogs and the hook must be precisely timed to coordinate their function with the movement of the needle. No variation is acceptable.
Harmonious synchronized movement of all the parts is essential. The sewing machine will fail to produce desired result every time disharmony occurs. When a needle breaks or when your machine is forced beyond its design, quite often the timing is knocked out of harmony and the machine immediately begins messing up.
When the hook is just slightly out of time with the needle, you will notice skipped stitches or no stitches. This may begin on only one side of the zig zag stitch or intermittently. If the timing is just a bit more out of sync, stitch formation will become impossible.
Move that fabric and keep it moving. If you ever felt that you had to pull you fabric through the sewing machine to make it sew, it was probably your feed dogs. They must be properly timed or they can not move the fabric appropriately. If the feed dog height is not also properly set, you will not get your desired result.
As you can see, timing is everything.
Following the analogy one step further, sewing machine timing may actually be more like a square dance. There are hundreds of individual parts all moving, turning, and operating all at the same time. Unless they synchronize their performances, the sewing machine fails to work. Two basic areas are concerned.
Initially, we see the synchronization of the needle with the hook. Together they move, dancing around one another. The hook wraps the needle thread around and dances off forming a stitch in time. Sewing machine technicians describe this timing relationship as hook-needle timing.
Next, the graceful motion of the feed dogs rises, glides back, drops, and rises forward in perfect harmony with the needle as she rises up and plunges below the needle plate. This is known as feed dog timing.
Indeed, just like an elaborate dance, the timing and coordination feed dogs, needle, and hook systems must work together in harmony. Even very small irregularities will distort or even halt the sewing process. Sewing machine timing is critical and must be adjusted and maintained in precise synchronization at all times.
To understand the timing of the feed dogs and needle, we can simply remove the presser foot and rotate the hand wheel forward. As it turns watch what happens. The needle moves from it highest point down toward the needle plate. The feed dogs reach their farthest point toward the back of the sewing machine. The feed dogs drop under the needle plate just before the needle point reaches the needle plate. The needle continues to move down dragging the upper thread under the needle plate, and proceeds toward its lowest point.
To understand the relationship between the hook and the needle, you will need to remove the needle plate and front cover. As the needle reaches the bottom of its swing and begins its rise back up; a loop of thread forms along the back of the needle. A special cut out on the back of the needle to accommodate this loop is called the scarf. The sewing machine hook slides behind the needle. The point of the hook slides into the thread loop and pulls the thread around the bobbin.
If you watch very carefully, you can see how the upper thread is drawn around the bobbin thread and then pulled tighter and tighter as the needle continues rising. When tensions are properly set, the two thread form a locked stitch inside the fabric. This same process continues stitch after stitch. Both the feed dogs and the hook must be precisely timed to coordinate their function with the movement of the needle. No variation is acceptable.
Harmonious synchronized movement of all the parts is essential. The sewing machine will fail to produce desired result every time disharmony occurs. When a needle breaks or when your machine is forced beyond its design, quite often the timing is knocked out of harmony and the machine immediately begins messing up.
When the hook is just slightly out of time with the needle, you will notice skipped stitches or no stitches. This may begin on only one side of the zig zag stitch or intermittently. If the timing is just a bit more out of sync, stitch formation will become impossible.
Move that fabric and keep it moving. If you ever felt that you had to pull you fabric through the sewing machine to make it sew, it was probably your feed dogs. They must be properly timed or they can not move the fabric appropriately. If the feed dog height is not also properly set, you will not get your desired result.
As you can see, timing is everything.
About the Author:
Sewing Author David Trumble shares the essentials of repairing sewing machines. He has authored several helpful sewing machine repair courses including a free beginners course entitled: 7 Steps To Peak Performance For Your Sewing Machine.
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