Here is a neat hobby that can turn into a real job or even a business. I am talking about sewing machine repair. There is a special thrill when a broken down sewing machine springs back to life almost like new " right in your hands. While there are challenges, it can also be loads of fun.
When you start tinkering with sewing machines, be ready to learn loads of information. There are literally thousands of different models and designs, but there are also some obvious similarities. One of the tricky areas of interest is the hook assembly.
A quick inspection of a sewing machine, and the technician can tell if the sewing machine hook assembly rotates or oscillates. These two types of mechanisms are very different, but perform the same basic function.
If your machine has a rotary hook system, it will continuously turn around. Turn the hand wheel and see it rotate. The way it works, is simple. As the needle starts back up, the hooks point catches the thread in the scarf (just above the back of the eye). It then draws the thread around the bobbin.
Where do you put the bobbin on this machine? I could be inserted in front, or top under the needle plate, or on the left end of the machine. If it is a top loading bobbin, the machine is usually a rotary hook machine.
A bobbin installed on the left side of the sewing machine may either have a rotary hook or an oscillating hook. The same is true of front loading sewing machines. For example, while Bernina sewing machines became famous for the CB Oscillating Hook System with front loading, they continue to use front loading on the high end rotary hook sewing machines.
If you are unsure what kind of hook system your machine has, rotate the hand wheel and watch the hook Oscillating hooks travel half way and then travel back. They move back and forth. Rotary hooks travel all the way around the bobbin carrier in a continuous rotation.
So to make sure what you have just answer this one question. Does it go all the way around as a rotary does, or does it go part way and retrace its path to start over as an oscillating machine does?
The Oscillating Hook Assembly involves a hook that begins a few millimeters to the top left and moves to the right sliding behind the needle and past it around to the bottom of the swing. Then the hook travels back again the same way to its original position for a return oscillation. Bernina sewing machines built their superior reputation based on their advanced oscillating hook system called a CB Hook.
Oscillating and Rotary hook systems do the same job. That job is pulling the thread from the needle around the bobbin carrier. The point of the hook slides behind and through the scarf of the needle to get the thread. Then it carries it to its destination.
The movement and positioning of the hook and needle must coordinate exactly. Slight variations result in skipped stitches, poorly formed stitches, or no stitches at all. The hook and needle travel through a finite pattern. For each stitch the hook and needle must align perfectly. As the needle rises, the loop must form on the back of the needle. The point of the hook must travel to precisely the right position and at the right moment for the hook to snag the upper thread. This is called Hook Needle Timing.
In about twenty percent of all standard sewing machine services, the hook-needle timing will need to be set. So, get use to this adjustment. It will be frequent. The cause of faulting timing can be traced mostly to user activity. Forcing the sewing machine to go beyond its intended use by pulling the fabric while sewing or sewing too thick a material is a common cause. Broken needles, wear and tear, Dirt, and debris are also common causes. To make this adjustment check your service manual for the model you are servicing. In time, you will gain confidence and do most adjustments without having to look them up.
The more you learn about how sewing machines work and how to repair them, the more sewing machine repair you can do. Just think there are millions of sewing machines just waiting to be serviced by somebody. You could be that somebody.
When you start tinkering with sewing machines, be ready to learn loads of information. There are literally thousands of different models and designs, but there are also some obvious similarities. One of the tricky areas of interest is the hook assembly.
A quick inspection of a sewing machine, and the technician can tell if the sewing machine hook assembly rotates or oscillates. These two types of mechanisms are very different, but perform the same basic function.
If your machine has a rotary hook system, it will continuously turn around. Turn the hand wheel and see it rotate. The way it works, is simple. As the needle starts back up, the hooks point catches the thread in the scarf (just above the back of the eye). It then draws the thread around the bobbin.
Where do you put the bobbin on this machine? I could be inserted in front, or top under the needle plate, or on the left end of the machine. If it is a top loading bobbin, the machine is usually a rotary hook machine.
A bobbin installed on the left side of the sewing machine may either have a rotary hook or an oscillating hook. The same is true of front loading sewing machines. For example, while Bernina sewing machines became famous for the CB Oscillating Hook System with front loading, they continue to use front loading on the high end rotary hook sewing machines.
If you are unsure what kind of hook system your machine has, rotate the hand wheel and watch the hook Oscillating hooks travel half way and then travel back. They move back and forth. Rotary hooks travel all the way around the bobbin carrier in a continuous rotation.
So to make sure what you have just answer this one question. Does it go all the way around as a rotary does, or does it go part way and retrace its path to start over as an oscillating machine does?
The Oscillating Hook Assembly involves a hook that begins a few millimeters to the top left and moves to the right sliding behind the needle and past it around to the bottom of the swing. Then the hook travels back again the same way to its original position for a return oscillation. Bernina sewing machines built their superior reputation based on their advanced oscillating hook system called a CB Hook.
Oscillating and Rotary hook systems do the same job. That job is pulling the thread from the needle around the bobbin carrier. The point of the hook slides behind and through the scarf of the needle to get the thread. Then it carries it to its destination.
The movement and positioning of the hook and needle must coordinate exactly. Slight variations result in skipped stitches, poorly formed stitches, or no stitches at all. The hook and needle travel through a finite pattern. For each stitch the hook and needle must align perfectly. As the needle rises, the loop must form on the back of the needle. The point of the hook must travel to precisely the right position and at the right moment for the hook to snag the upper thread. This is called Hook Needle Timing.
In about twenty percent of all standard sewing machine services, the hook-needle timing will need to be set. So, get use to this adjustment. It will be frequent. The cause of faulting timing can be traced mostly to user activity. Forcing the sewing machine to go beyond its intended use by pulling the fabric while sewing or sewing too thick a material is a common cause. Broken needles, wear and tear, Dirt, and debris are also common causes. To make this adjustment check your service manual for the model you are servicing. In time, you will gain confidence and do most adjustments without having to look them up.
The more you learn about how sewing machines work and how to repair them, the more sewing machine repair you can do. Just think there are millions of sewing machines just waiting to be serviced by somebody. You could be that somebody.
About the Author:
Get more detials on repairing sewing machines Dr. David Trumble. Explore his extensive curriculum of sewing machine repair courses. Pick up your own free copy of his beginning course 7 Steps To Peak Performance For Your Sewing Machine.
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