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.
Find the bobbin on the sewing machine. Look under, around, or behind it to find the hook. Rotate the hand wheel forward and watch the hook move. How does it move? If it moves in a complete circle around the bobbin it is a rotary hook assembly. If you look closely, you can see that as the needle comes down and starts back up, the point of the hook slides behind the needle just above the eye. It picks up the thread and pulls it around the bobbin.
When you look at a sewing machine, look for where the bobbin is inserted into the sewing machine. If the bobbin is a top loading bobbin (one placed just below the needle plate and a slight bit in front of it), it is usually a rotary hook.
Both the front loading and side loading machines can have either hook system. A good example of the side loading machine is the popular Singer Featherweight. Bernina is famous for their front loading CB oscillating hook system, but they also produce front loading rotary systems.
A rotary hook moves around in a continuous circular motion. An oscillating hook moves back and forth. How can you tell which type of sewing machine hook assembly you have?
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?
Watch closely. The point of the oscillating hook starts just a few millimeters to the left of the needle when it reaches its lowest point. As the needle rises, the hook moves behind the needle. A loop of thread forms in the small cut out on the back of the needle running above the eye called the scarf. The point of the hook grabs the thread here and pulls it around to the bottom where it releases the thread. It then oscillates back to its original position for another stitch. Bernina used their special patented CB Hook to become a premium sewing machine line.
Both systems do essentially the same thing. As the point of the hook passes behind the needle, it is positioned slightly higher than the eye of the needle. The upward travel of the needle causes a small loop of thread to form on the back side of the needle above the eye and amplified by a space called the scarf which is cut out above the eye. The point of the hook snags the thread from behind the needle and pulls it around the bobbin thread. As the needle rises, the threads are tightened into a lockstitch.
Each part must work in perfect timing and coordination. The hook assembly and needle must reach their exact connection point on every stitch precisely when as where they are suppose to. This is called hook-needle timing. When they are out of synch or time, you will see skipped or potentially no stitches formed at all.
Adjusting the hook-needle timing is a very common adjustment. If the user breaks a needle, sews on excessively thick material, or debris builds up in the gears; the timing often gets jolted out of adjustment. The specifics of making this adjustment vary considerably from one model to another. Some adjust on gears located directly below the hook. Some adjust at the side or at the end of the lower shaft. Some use timing belts. The essential adjustment is always the same, however, in that the point of the needle must reach the scarf at precisely the right time and in the right way. Check the specific service manual for details on adjusting the hook-needle timing until you gain enough experience and knowledge to adjust it on the fly.
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. - 15465
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.
Find the bobbin on the sewing machine. Look under, around, or behind it to find the hook. Rotate the hand wheel forward and watch the hook move. How does it move? If it moves in a complete circle around the bobbin it is a rotary hook assembly. If you look closely, you can see that as the needle comes down and starts back up, the point of the hook slides behind the needle just above the eye. It picks up the thread and pulls it around the bobbin.
When you look at a sewing machine, look for where the bobbin is inserted into the sewing machine. If the bobbin is a top loading bobbin (one placed just below the needle plate and a slight bit in front of it), it is usually a rotary hook.
Both the front loading and side loading machines can have either hook system. A good example of the side loading machine is the popular Singer Featherweight. Bernina is famous for their front loading CB oscillating hook system, but they also produce front loading rotary systems.
A rotary hook moves around in a continuous circular motion. An oscillating hook moves back and forth. How can you tell which type of sewing machine hook assembly you have?
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?
Watch closely. The point of the oscillating hook starts just a few millimeters to the left of the needle when it reaches its lowest point. As the needle rises, the hook moves behind the needle. A loop of thread forms in the small cut out on the back of the needle running above the eye called the scarf. The point of the hook grabs the thread here and pulls it around to the bottom where it releases the thread. It then oscillates back to its original position for another stitch. Bernina used their special patented CB Hook to become a premium sewing machine line.
Both systems do essentially the same thing. As the point of the hook passes behind the needle, it is positioned slightly higher than the eye of the needle. The upward travel of the needle causes a small loop of thread to form on the back side of the needle above the eye and amplified by a space called the scarf which is cut out above the eye. The point of the hook snags the thread from behind the needle and pulls it around the bobbin thread. As the needle rises, the threads are tightened into a lockstitch.
Each part must work in perfect timing and coordination. The hook assembly and needle must reach their exact connection point on every stitch precisely when as where they are suppose to. This is called hook-needle timing. When they are out of synch or time, you will see skipped or potentially no stitches formed at all.
Adjusting the hook-needle timing is a very common adjustment. If the user breaks a needle, sews on excessively thick material, or debris builds up in the gears; the timing often gets jolted out of adjustment. The specifics of making this adjustment vary considerably from one model to another. Some adjust on gears located directly below the hook. Some adjust at the side or at the end of the lower shaft. Some use timing belts. The essential adjustment is always the same, however, in that the point of the needle must reach the scarf at precisely the right time and in the right way. Check the specific service manual for details on adjusting the hook-needle timing until you gain enough experience and knowledge to adjust it on the fly.
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. - 15465
About the Author:
Get more detials on repairing sewing machines Dr. David Trumble. Check out 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.
