Internal Thread Wrap = Locked-up Longarm!
Thread - your friend when in the quilt sandwich. Not so much when in your longarm...
I was recently summoned to a longarmers studio with a longarm that was completely locked up - it would not rotate at all in either direction. The machine was being operated by a computer-guided system, and she stepped away for just a minute, heard it make a funny noise, slow down, grind, and then stop. She was pretty sure the thread had broken and had got sucked into the interior of the machine through the slot the take-up-lever cycles up-and-down through.
After doing the normal outside checks, I opened the machine and saw the quilter was spot-on - there was a thread-wrap around the counter-weight/articulating link area that had become wrapped so tightly it locked down the needle shaft from rotating. (Pic 1).
After several (yes several) minutes of snipping, pulling, and extracting with precision tweezers the thread was removed and the machine was able to rotate normally. Nice little thread nest...(Pic 2).
To add insult to injury the "event" had knocked the hook/needle timing off - got it reset and the longarmer was back in business.
Moral to the story - if you are free-motion quilting from either the front or the rear pay attention to the sound of your machine and the movement of the thread - if the thread vanishes stop immediately and if it was sucked into the interior you will likely be able to pull it out before it wraps around one of the rotating or cycling components. If you are operating the longarm with a computerized system and step away to find the machine stopped and either the thread ingested into the interior or missing entirely and the machine locked up, you likely have a thread wrap that will need to be removed and the timing of the machine verified and reset if needed.
Quilt on!
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