Superior So Fine! Polyester Underthread

Imagine a thread with the look and feel of cotton, but without the lint. That is exactly what So Fine! Is – an extra soft #50 polyester thread that is etched in order to give it the look and feel of cotton thread.

As a thread person, I rate this thread along with Superior's 'Bottomline' as an underthread of choice. Ever so slightly thicker (therefore stronger) than Bottomline this thread ticks all the boxes.

A filament polyester underthread has a shiny appearance and is virtually lint free, thin and lightweight, yet strong.

Embroiderers love this thread because it creates a soft backing, even on dense designs with many machine quilters liking it due to its smooth surface.

A filament bobbin thread works exceptionally well with all threads, balancing them perfectly, it is also the underthread of choice if you are using metallic threads or heavy cotton threads. The smoothness of the filament poly thread does not snag or grab the top thread. If you've had trouble using metallics or heavy cotton threads, a smooth bobbin thread may solve some problems.


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