Originally Posted by OzarksGma

I use Superior Mono Poly in the bobbin as well as on top and it quilts beautifully on my HQ16. Don't overfill your bobbins as the invisible thread tends to swell after filling and will pop the sides off plastic bobbins. May cause metal bobbin to warp out of shape on sides. I use my TOWA guage to set the bobbin tension as I change threads with every quilt.