Jamie W has a tool that can be used to check round and even help to get cases back in shape if they are not too badly bent. I bought a second case when I was having so many problems, but I'm back to using the original as it was not the problem. I like having a spare case on hand just in case.

https://www.youtube.com/watch?time_c...&v=SlMgxd2bXwY

Bobbin Dewarper.

Something I found out recently too is that your bobbin should sit up just a little above your bobbin case. Is the spring at the bottom of your case missing? If not you may need to adjust it a little. Sure helped my tension when I did that. There's a video on the ABM website that shows you how your bobbin should sit inside your bobbin case and how to adjust the springy thing on the bottom, just have to bend it a little.

Mine do not have the hook thingy (technical term?), just an opening for the thread.

This is so confusing and frustrating to have different techs and repairmen saying opposite things.
I took the spring out of my bobbin case and my tension issues cleared up and I haven't had any more problems. I was told by a tech to take it out and use a bobbin geni washer instead. When I took it in for a cleaning the repairmen put in a new one,said it was missing. He said the tech was wrong. I said well it works for me so out it came.

The tension spring is easy to remove and put back. I took it out of my Bernina and Brother 1500.

Watson--like others have said an "out of round" bobbin is easy to find when you use the Towa gauge--maybe you can put that on your Christmas wish list? It really makes things easier. Also, Jamie Wallen is who I bought the bobbin tool to check that there isn't a flat side on it from being dropped--think it's on his website too.

I have a new to me long arm machine and am having some trouble with the bobbin becoming jammed. Don't know how else to explain it. The thread won't pull so that the machine can be moved forward. Wonder what is causing that. After reading your comments above, I am going to check some of those ideas as possible solutions. So frustrating trying to trouble shoot when we don't know what is causing the problem. Thanks for any helpful hints.

Do you mean you can't pull up the bobbin thread? Can't understand the way you are explaining it. So say you were quilting along and now you want to stop and tie off your threads and you can't move the machine head because the bobbin thread won't release? If that is the case, check the position of your take up lever. It should be almost all the way up with say about a finger width between the top of the machine head and where the take up lever is resting. Sometimes, even with your needle up, that take up lever hasn't done a full cycle and isn't in the fully up position it is sitting at the half way point. My machine has a jog function that resets it so the take up lever is in the fully up position when my needle is up and I have stopped the machine. If your machine doesn't have that, you have to manually turn hand crank to get that take up lever in the fully up position which will release your bobbin thread.

Watson, I wanted to check my LA bobbin case before I responded. I always load my bobbin into the case like your 2nd picture. It is my understanding that little hook on the end of the spring that goes into the hole is simply the only way to hold the tension spring at a consistent tension on to the bobbin case itself. I don't believe you should be wrapping your thread around it like you do in the 1st pic and quite honestly I strongly suspect after your machine takes its first stitch the thread moves to the position of your 2nd picture. Try an experiment, load it the way you normally do and stitch only a few stitches on a test sandwich and then take your bobbin case out and see where the thread is. I bet you it looks like your 2nd picture. One thing I do always make sure of is that once I drop the bobbin into the case and thread under the spring, I make sure my bobbin is always rotating in clockwise rotation.

I looked closer at on of my bobbins and there is something that looks like the hook, but, it is pressed flat into the hole and against the inside of the bobbin holder, it does not hold the thread, the thread slides over it into the hole.