Thread bunching on bottom! Only doing it when sewing heavy nylon webbing. Doesn't matter the thread or bobbin or needle (already switched out). Sews fabric fine. Was working fine days ago on
Best Thread for Upholstery | OFS Maker's Mill
Gutermann Sew-all Sewing Thread - 264 Khaki
Nylon Thread Buying Guide
How to Sew Webbing Loops
How to Sew Webbing: 12 Steps (with Pictures) - wikiHow