Sewing Machine Repair may be as simple as replacing a needle, but it can be much more involved. Here is a Brother CS80 with covers removed so you can see what it looks like inside. You will notice that it has a shell construction rather than an internal frame or skeleton. Many lower end sewing machines are made this way today. It is less expensive to make and buy, but ii is also not very durable. This machine has a rotary hook assembly with a top loading bobbin. In most cases, adjustments are mechanical although the machine has circuit boards, pulse motors, and some computer control. .
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