Serger issue - unwanted flatlocking!

[vepoppins]

Hello, everyone! I'm here to pick your brains on that bane of the sewing world for beginners - the serger.

I've been using mine for most of the summer; figured out how to thread it, made lots of lovely, sturdy dresses, etc. However, a wrench was thrown into the works today when I attempted to change threads. The new thread is the exact same cotton as the previous thread I'd been using. I followed the instructions on how to rethread the machine, but snaffued when I rethreaded the needle. I pulled the threads through and completely rethreaded the machine, but when I began sewing again, instead of its normal stitching, I was able to pull apart the two pieces I'd just sewn together. I think this is either the same as or very similar to flatlocking - trouble is, I'm going for a sturdy stitch, not an embellishment!

Since the initial discovery, I've rethreaded the machine and fiddled with the tension for at least two hours, and there's been no change in the machine output. I'm using only one needle (the left), and it worked splendidly earlier this summer.

So - anyone have any ideas? I'm absolutely open to hearing them!

[vepoppins]

Never mind! After more fiddling, I got it working again. The secret, if anyone has the same problem I did, is to make sure your needle thread is securely between the tension disks!

See? Simple like the boogaloo.

[ms.shell]

i'm glad you solved it. stuff like that has happened to me lots of times. i thought i broke my new serger recently because all of sudden the rolled hem was making a nasty mess, when it had always been beautiful before.
finally figured out i had forgotten to change the stitch length to R. lol

i always use the right needle only when using 3 threads.