A lot of the sewing machines available in the market today come in plastic frames. It is understandable because using plastic to build the machine frames is a cheaper option. There is also a benefit to having a plastic frame. It would be easier to carry your machine around when you need to. Some Brother sewing machines today come with a metal frame under a plastic case. Some do not come with metal frames anymore but only use plastic as a frame for the sewing machine. Plastic sewing machines are less expensive than metal machines since plastic machines are cheaper to make. Also, they are lighter and easier to carry around for sewing lessons or sewing club meetings. The vintage metal sewing machines are known for durability but are also expected to be pricey and harder to find. Modern sewing machines with plastic frames have many options to choose from and come with automatic features. Despite being more advanced, you can still buy them cheaper than their metal counterparts.