A few years back I made some clear curtains for my boat. My old Kenmore worked OK to good. Although, my first attempts sucked. I got pretty good at it and finished my project. I am getting ready to sew clear inserts. I suspect 20 gauge will do. 10 gauge too light and 30 gauge too thick. I cannot remember what gauge of clear I used. I will have to sew zippers onto vinyl. Any suggestions?