How old is too old for serger thread?
 

I was instructed by my new friends (the proprietor and the teacher at the local sewing machine place) to not use old serger thread, but then I accidentally bought some from them that was made in 2008. Seems pretty old to me! But my question is does it really matter for polyester Maxi-Lock serger thread? I'm using it on items I intend to sell, and I would like my product to stand up over time.

On a related note, if I use fresh thread, will the item I use it on break in ten years, since the thread in the product is now old? Should I make a point of using cotton thread in the needles for more durability and save the polyester for the loopers? Mostly I make bags and pants, so they get plenty of wear and tear.

I haven't opened the thread yet, I was afraid the store wouldn't honor a return if it was unwrapped. Maybe I can pull a little bit out from underneath...

I'm with Tartan on this. But when buying thread make sure it is not displayed in or near a sunny window or under bright lights. Even the non-cotton threads get brittle.

If you have a lot of it, and it wasn't too expensive, break one open and try the test. If it was expensive, stick a crochet hook through the cellophane and pull the thread.

Sometimes the people in a shop tell you what will get you to buy new from them. Be it brand or other things.

A few yrs ago I wanted to use my serger thread to do some FSL projects on my emb machine so that it would be cheaper and since it was for kids didn't want to spend a fortune on thread knowing the project would be around long. At first it would do good, then break there was no ryhme or reason as to when it would do this. So I thought ok, the thread is close to 18yrs old I should get new thread, I did and I got the same results. Took me a while but finally figured out to change the needle to a larger size and slow it down. I'm now back to doing serger projects and use old and new and it never breaks on me. If my thread were constantly breaking then I'd probably worry but it takes a lot of stress on the thread going thru a serger so if it doesn't break in the machine I wouldn't worry about it. Like I said, most of mine is around 18yrs old.

I had recently bought some from Joann's and it started breaking so I took it back and they had no problems refunding my money.

Thanks for the suggestions, everyone. It was from a small shop, so if they refuse a return, it occurred to me that I can use it in the loopers and use my regular sewing thread for the needle where strength is most important.