While there are a handful of different timings in a sewing machine, the hook timing is the most common to cause a sewing machine to not function correctly. Hook timing is the relationship of the hook tip and the needle eye. If you think your sewing machine may have a timing problem, a careful examination of the hook and needle can confirm that condition.
When the needle is moving upwards, it creates a loop behind the needle, between the needle eye and the fabric. The hook tip must pass through that loop in order to create a stitch. There is a fine tuning of the hook timing, depending on the brand and model of the sewing machine, but nearly all sewing machines adhere to this basic principle.
In order to check the hook timing, it is important to see which direction your hook rotates as the needle is in its upward ascent. If your hook is turning clockwise, such as with most oscillating hooks, you will want to adjust your needle position to the far right.
Janome rotary hooks are always turning in a counter-clockwise direction. For these machines, adjust the needle position to the far left. Any other hook that is turning counter-clockwise should also have the needle in its far left position.
In the images below, notice that the hook tip is above the needle eye as the hook passes behind the needle. Click either picture to zoom in.
If your hook tip is passing through or below the needle eye, then the timing of the sewing machine is off. On the other hand, if the hook tip is passing above the needle eye, but extends past the needle more than a couple of millimeters when the needle eye meets the radius of the hook, then the timing is also off. In either case, you will probably need to bring your machine to your local sewing machine technician.
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