Vintage Singer 66 sews 4mm leather amazing results with this threading method watch and see.

I've been testing this Singer model 66 sewing machine attempting to sew heavier materials like 4mm leather and have come up with a slightly different threading method to create a bit more upper tension check it out. You will need a size 18 needle and some T90 thread of good quality to get these results. Timecodes 0:00 – Intro 0:40 – Needle and thread I’m using size #18 and B92-T90 thread. 0:53 – Adjustments made to bobbin tension and threading the machine 1:05 – Sewing heavy material Singer 66 sewing machine. 2:44 – Sewing 4mm thick leather with the Singer 66 sewing machine. 5:15 – Final test run all adjustments made.