Bonded thread is typically a two, three, or four-ply construction coated with resin that makes filaments twisting more tough with a uniform finish which prevents the ply ends from unraveling in the reverse direction. Besides adding abrasion resistance and smooth stitching, the resin coating improves environmental resistance like heat tolerance, chemical and mildew resistance. Therefore, bonded thread outperforms non-bonded thread in most heavy fabric applications where bonded thread is always the superior choice.
1. To find right needle for heavy duty bonded thread, you'e better to ensure the eye of the needle is 40% larger than the thickness of the thread. This will allow the thread to pass through the eye without trouble.
2. Polyester and nylon bonded threads including tex 90 bonded polyester thread and tex 45 bonded nylon thread usually have very similar tension characteristics as long as they are the same size. This means they are close enough in specs to generally not need tension adjustments when changing between them.
3. Please keep in mind that not all bonded heavy duty sewing thread is meant to be used with every type of fabric though bonding resulting in a more advanced technical sewing thread. Under no circumstance should you use the stronger bonded thread to sew silk since it may excess grab the fabric and be more visible. So it's vital to match thread to fabric to be sewn. Generally speaking, using polyester thread for synthetic blend materials, cotton thread for natural fabrics, and silk thread for silk materials.