Is there any reason not to use old sewing thread?
After a long interval, I’ve recently decided to take up sewing again and bought a new machine. The spools of thread that are meant to be used with it look like this. [ new thread ]
I still have a quantity of cotton thread in assorted colors that look like this. [ old thread ] Some of it is 20 years old. Some of it might be a lot older than that.
Disregarding size and shape of spool, is there any problem with the age of the thread itself? Will using it ruin anything? Theoretically at least, is there any reason why I shouldn’t use thread that’s 50 years old?
Do I have to throw it all away and start over?
What if I use old thread for bobbins and new thread for the top spool?
This question is in the General Section. Responses must be helpful and on-topic.