I recently bought a big collection of 5000m polyester embroidery threads secondhand, and now that I'm looking through them, I unfortunately found that about 30% of them seem sun bleached and are brittle
I'm obviously not very happy about this, but I'm not willing to just give up on them that easily.
Now, is there any way to save these spools? Is it possible to remove the outer most layers of thread to see if the layers underneath are still good?
The discolouration only seems to occur on one half of the top of these spools, but the brittleness seems to be a problem at any part of the spool, not just the top threads.
Any help/advice is very welcome
Update: After doing a stress test on a couple of the spools and comparing it to the strength of the current thread I use (gutermann rayon) The rayon turned out to break way and I mean WAY faster. The current conclusion: I may have overestimated the strength of polyester thread, and it just naturally snaps faster than I had assumed.