Originally Posted by
TeresaA
I suspect that there's something blocking the top thread path. Could there be a bit of thread stuck in the tension mechanism?
This is what causes similar problems in one of my machines at times. If you are showing us the bottom side, it's the top tension that is not feeding the thread correctly. I know that's counterintuitive because the top side of the stitches may actually look quite normal. I don't really understand the logic of machine designers who have made the thread path out of sight for us, so that what might have been a simple problem on an old fashioned machine is completely inside where we can't see it and can't get at it.
The first thing I can suggest is to try a technique when threading it a bit like when you floss between your teeth. Be sure to hold the thread firmly above and below as you pull it through the area where the tension is, so that it has a better chance of engaging. The presser foot should be up when threading so that the tension is disengaged and the thread can get in. The manual will probably specify where it's important to hold the thread firmly as you thread it. If that doesn't work, you may need a technician. If you're lucky, maybe you can find a tech person who will do a diagnostic while you wait and charge a small fee if all he/she has to do is pull out the snarl with tweezers. This is not covered by the Brother warranty (I was told), because it's considered user error. It's certainly an argument for quality thread, but even the best ones will sometimes have a flaw. My Brother is an embroidery machine, but the thread path is very much the same as on my Singer and Baby Lock machines.
If (and only if) the machine is out of warranty, you could look around for a screw or two that might give you access to that area yourself. I have been able to pull out a snarl from my tension (on a new-ish Singer) using a tiny steel crochet hook. Don't bend, scratch or force anything! Unplug first, of course. If you see thread inside there when the machine is not threaded, that's pretty solid evidence of what's wrong. When I did it, I found a short piece of thread wound tightly at least 30 times. It was worth my time to deal with it only because the Singer repair place was an hour and a half away.