Does Poly thread cut Cotton Fabric?
 

Here is another, what I call quilting myth. The word has been around for years that one should not use poly thread or poly wrapped cotton thread when using cotton fabric. Something about "in time it will cut your fine quilts". I decided to really check this out. I was at a quilting event last week and stopped in one of the thread booths and ask the owner of the thread company the question. His first answer was "does the poly thread which blue jeans is sewed with cut the fabric?" I told him that was not a good example because the denim is a much heavier and stronger fabric. then he said his company had sewed on cotton thread with 100% poly thread and washed it about 50 times and there was no indication of the thread cutting the cotton fabric. This answer is good enough for me. and then I don't make quilts that will end up in a museum or still being used in the future however long that might be.

The quilters that believe this I just let them talk about how bad poly is. They sound foolish enough without me having to disagree with them.

I know that sowing particular fabrics you need to be careful of which thread you use. That being said, none of those fabrics are used for quilting. I have recently switched to poly and I am a happy camper since the lint is negligible and I can get poly anywhere.

Isn't amazing how quilting myths come about? I have read many posts on here that quilters are not supposed to use polyester, ever! Only use cotton. Yet, garment sewers use polyester or cotton/polyester blends and think nothing of it. I think it's inportant to try different threads to see which ones you like best.

I imagine it may cut cotton after 100 years--that's a maybe. I don't know for sure.

I don't believe it.

Superior Thread has a demonstration in a video where the poly thread tears before the cotton thread does. This myth needs to be debunked.

It isn't a myth, I have three quilts that prove it can happen.
Just washing two sewed pieces of fabric 50 or 500 times will never cause the thread to cut the fabric, it is the weight of the three layers shifting over time and washes and wear that create the cut.

Some reasons the perfect storm can converge are:

using worn clothing for the patches
flat fold thin fabric for the patches
quilting too far apart for the batting selected.

It probably won't come up if the fabric is good quality and I think we all agree price isn't the only factor in fabric.
If the quilting stitch is mid-range rather than too tight
Consistent full seam allowances.

All that said I've been making quilts since 1970. Some of those early quilts were just like beginners quilts today.
The difference is, 1970 was a long time ago and my quilts are used and washed often :) so I've had time to see what happens
any quilt folded in the closet or under the bed will probably last forever, regardless of materials, skill and use.

Cotton thread will let go before cotton fabric does. Those problems are super easy to fix. patches cut on the sewing line are a booger to repair.
That said, I am happily using up all my coats and clark poly cotton thread because the quilts I'm making today won't have to hold up to lots of everyday wear because I have a lot of quilt and switch them out every month.

Quilt police is the myth I don't believe. The only quilt police are in our head. :)

I've had the seam wear and the thread still be good in clothing, including jeans, plenty of times. Of course you have to have something and wear it for years and years for that to happen.

The cotton fabrics become weaker over time by use and washing. The truth of the matter is this: the stronger fiber will always win! Its not that the poly thread "cuts" the fabrics; the cotton fabric becomes weak and deteriorates.

http://www.superiorthreads.com/educa...dition-or-myth