Why is the zip is curved/humpy after pressing?
Spiral/coil zips have an S twist and Z twist in the teeth creating a “smile” or “frown” appearance when the teeth are joined. The left and right teeth should be both in the same direction/condition. If this is not the problem check the sewing tension is equal on both sides of the zip. Also check […]
Can I add lubricant/silicone to the thread?
Coats does not recommend adding any additional lubricant/silicone to thread. It can change thread color and cause variations in friction, resulting in oil stains. Atomized silicone may also pose a health issue if inhaled by operators/machinists.