The only problem with using polyester thread to piece with is that the
melt temperature is lower than cotton. If you are using a really hot
iron, with fairly long pressing time you are liable to melt the
polyester thread. G Not what you want to do at all.

Pati, in Phx whose first quilts were pieced with poly serger thread. VBG

Kate XXXXXX wrote:

It depends what type of Gutterman it is... If it's their All Purpose
Sewing Thread, then yes, though it IS polyester and I'm not keen on it
for piecing (that's just personal choice). If it's their cotton thread,
use it for either piecing or quilting. They also do silk thread, which
I use mostly in silk garment construction, a waxed cotton hand quilting
thread, embroidery thread, Topstitching thread (which is thicker) and
serger threads... Take a look at your reels: the different types of
thread are on different coloured reels, and are also labelled on the ends.