Quote Originally Posted by Barb T. View Post
Wool is a little stretchy, too, so I'm guessing that polyester might be a better choice than cotton for the same "give" factor.

I did find a lot on the Internet about the deterioration of silk fabric and thread over time. So, I don't think you want to put a lot of work into a kilt and have the silk thread rot on you.

So, I think 100% polyester for wool or poly-wool mix is the best.
The problem with the deterioration of silk is mostly seen in silk fabrics from the 1800 to very early 1900s (and inexpensive silks to this day). The manufacturing process changed to add metal salts to the fabric as it was finished. A "moderately" weighted silk fabric can have up to half its weight be the salts! These salts (often tin phosphate/ sodium silicate or tin chloride) increase the density of the cloth, improve the hand/drape, make it rustle and enhance the surface shine.

The problem is that over time, the salts change the chemical composition of the silk protein and make it brittle. I've seen c1850 crazy quilts where the cotton and wool patches and the silk embroidery threads are still pristine, but the silk dress fabric patches have literally shattered underneath the embroidery. You guys may see this in old bonnet cockades and ribbons.

Plus silk sewing thread is almost impossible to find, most silk thread these days is meant for embriodery, not sewing. One more thought on poly thread, though. It doesn't hold up as well to high heat as threads made of natural materials, so use those press cloths!

Barb - I hadn't thought about the 'give' factor! Again, a plus for the poly thread. So Gutterman's or Mettler for me.