I found this ewrap by Kamalini Trentham for machines like the Brother that you can pull the needles all the way out to hold position and then knit one row. I decided to do it on the passap machine. I first cast on with waste yarn. Then I knitted one row of ravel cord at loose tension. I pulled all of the needles all the way out as far as they come. You take two different colors of yarn and tie ends together and start at the left to ewrap first with one color and then the next color all the way to the right. The important thing here is to make sure the yarns are crossed and the wrapping colour lays over the top of the wrapped color. When you are finished, you can’t knit these back with the machine so you hand knit the first row to the left. Bring the carriage across on G/X setting and start knitting your garment. This is a nice flat edge and there is no bulk or pulling. I think you can go any thickness of yarn for this since you will be hand knitting the trim back. On my sample, if I was to make a simple sweater I think I would double the strands of each color for a little more thickness. The black you see in the picture is just the background color to make the trim stand out.