Many people have no way to distinguish the heavy material sewing machine from the medium heavy material and thin material sewing machine from the model. Here are a few different points to distinguish them.
1. The amount of thread take-up is also different. Thick material sewing machines generally use DP needles, and medium and heavy material sewing machines use DB needles, because the needles of thin material machines are thicker than those of thick material machines.
2. The speed of sewing machines for heavy materials is generally slower than that of sewing machines for thin and medium materials
3. The pagoda spring of the thread clamp of the heavy material sewing machine is stronger than that of the medium thick material and thin material sewing machine
4. The rotary hook of the heavy material sewing machine will take off the thread earlier than the thin material and medium heavy material sewing machine..