Most think that you can only do a rolled hem with wooly nylon in the upper looper. Not so. I often use regular serger thread in the upper looper especially if I need a perfect color match. But there is a trick - isn't there always.
The upper looper thread tension needs to be adjusted to just a little tighter (higher number tension). Sometimes you need to tighten the needle thread tension just a wee bit too.
My sister Karen drives me crazy - she rolled hems everything because she is too lazy to hem on her conventional sewing machine. AND she refuses to use any of the decorative thread I have given her. SO - she uses regular serger thread to do rolled hems on robes, blouses, vests, shirts and so on. But of course she always calls me and asks - what should I set the tensions at for a rolled hem?
OH - and there is a wooly nylon that is a heavier weight. I have used it to edge tapestry pillows. When all four sides are complete - it looks like piping. I think it is called wolly Extra. Not sure. I have a couple of spools in my sewing room, but I am too tired to go downstairs and look.
You can also use Jeansstich thread by YLI - but you will have to lengthen the stitch a little. That thread is heavier weight than the others I mentioned above.
Have a great weekend everyone. We are expecting snow??? SO I will SEW!