How to Adjust Oscillating Hook Timing.

How do you adjust an oscillating hook timing on a sewing machine?

An oscillating hook is a sewing machine hook that rotates half way around. It stops releasing the upper thread.  Then the hook rotates back to its starting position.  It is important that you understand oscillating hooks for proper sewing machine repair.

This is very similar to the oscillating patterns used by the much older shuttle machines.  In the antique shuttle machines, a long bobbin is wound full of thread and inserted inside the shuttle mechanism.  In the sewing machine, the shuttle is typically mounted on a long arm that moves back and forth beside the needle.  The shuttle picks up the thread loop from behind the needle and slides it over the bobbin to create the lock stitch. Proper adjustment is critical for sewing machine repair.

How do you adjust an oscillating hook on a sewing machine?

There have been hundreds of sewing machine models using the oscillating hook system.  Most of the oscillating hook sewing machines today have bobbins that fit into a bobbin carrier that detaches from within the hook assembly.  These machines may be left side loaded, but more commonly are front loading machines.  Sewing machine repair technicians must understand oscillating hooks.

How do you adjust an oscillating hook on a sewing machine?

Commonly, a door covers the sewing machine hook assembly.  At the touch of a finger the door opens to reveal a bobbin carrier.  Usually the carrier (with a locking latch across its center) is mounted attached to a center post protruding from the center of the hook.   Popular brands using the oscillating hook system have included Necchi, Dressmaker, Janome, and Bernina among other brands.  Bernina sewing machines patented their CB hook system, and became a leading quality sewing machine brand.  Bernina sewing machines are often describes as the “Cadillac” of sewing machines. This is important for sewing machine repair.

How do you adjust an oscillating hook on a sewing machine?

The oscillating hook assembly is often considered superior to the rotary hook system, because it often produces a more stable and higher quality straight stitch.   Today, however, high end sewing machines have abandoned the oscillating hook system.  Due to stitch width limitations of the oscillating hook system, and certain other limits the rotary hook system prevails.  Sewing machine repair must take this into consideration.

How do you adjust an oscillating hook on a sewing machine?

Here is the basic procedure to adjust the hook needle timing.  Set the point of the hook so that it picks up the thread loop behind the needle.   This is a vital setting for sewing machine repair.

Set stitch selector to zig zag and stitch width to its maximum.

Remove the Bobbin Carrier, Bobbin, and Shuttle race cap (mechanism that holds the hook in place).  Leave the hook in place.  Note you may have to hold it in place with your finger while you make adjustments.  Make the proper sewing machine repair.

Rotate the hand wheel toward you until the needle reaches its lowest point in the far right needle position.

Rotate the hand wheel slowly until the needle enters its upward swing.

How do you adjust an oscillating hook on a sewing machine?

The hook should begin turning clockwise (from left to right). As the needle rises, watch closely to see the point of the hook move behind the eye of the needle. Note the tip of the hook should be 0.5mm above the hole in the eye of the needle. If the gap is too small or too large, it will need to be adjusted. Repeat the same process and observe the far left needle position.  Generally, if the point of the needle moves behind the needle scarf properly, it will pick up the thread loop and form the stitch.  Adjust properly for sewing machine repair.

How do you adjust an oscillating hook on a sewing machine?

Here is an alternate approach to adjusting the hook needle timing.  Rotate the hand wheel to move the tip of the hook to the farthest left movement .  Measure from the point of the hook to the needle just as the needle begins its rise.  It should measure 2mm.

The hook must be able to pick up the thread from the extreme left and right needle positions.  This is vital for proper sewing machine repair.

Adjust the rotation when required.  Look for a lower drive shaft on the bottom of the sewing machine.  Observe how it oscillates back and forth driving the hook to do the same.  Loosen the adjusting screw on the drive gear.  Manually move the hook to its appropriate position. Retighten the adjusting screw.

After setting the hook needle timing. Run the sewing machine a minute or two and listen carefully.  Listening is an important skills for sewing machine repair.

If you hear a slight ping. The needle and hook are too close together.  They are actually touch slightly creating that pinging sound. The hook needle distance must be adjusted accordingly. They should be as close as possible without touching or producing a ping as they pass.  Adjust properly for effective sewing machine repair.

How to Adjust Oscillating Hook Timing.