I've not used a double needle in my regular machine either....was just thinking about it as I have to be repairing a leg on my sons dress pants. I have no clue how to do it. You can see the double needle that threaded the rest of the seam. They don't have to be nice looking, it's just the bottom of one pant leg....but he has to have dress pants for his upcoming choir concert and he ripped the side seam on his only pair.
All of his ripped jeans are going to magically turn into shorts for the summer....mostly cause I don't know how to repair anything. I won't patch knees, been there done that...just gotta figure out this seam thing. Clothes are so much harder than quilts!