This may seem wasteful but I change my bobbin every row when doing pantos. I hate getting into the middle of a row and run out of thread. I always check my bobbin when doing freehand work after I finish a certain portion of any quillt. I would rather finish an area and cut, knot and bury the thread rather than have to unsew several inches of finished work to get enough thread to knot and bury.

This is a lesson I learned with a lot of practice and yes the end of a bobbin doesn't sew as nice.

I transfer leftover thread to bobbins for my DHM for quilting small projects so I am not really wasting a lot.
peace

Ube quilting, I do that too...I wind my own bobbins and usually one bobbin is enough to do a row with a little leftover that I don't use...then I use a new bobbin
it saves me time...it takes longer to unstitch part of it then, join carefully, than it does to start with a fresh bobbin and know you won't run out...it only wastes a bit...

I like this tip. I usually just nail it, instead of burying in the middle, but I think I may wind less on the bobbin and change at the end of each row. That will solve several problems.

+1 on changing by choice and not because it ran out. I find that the tension changes as the bobbin decreases I size. I just finished a heavy custom and found one block that has issues. May be my backlash spring in the bobbin case needs to be changed. The remainder of the quilt had perfect tension and done by computer, so the speed was consistent. Sometimes, I just forget to check it though. So many little things to remember. I have been trying to do pre-emotive bobbin changes to prevent a thread break in the quilt where it might be noticed.

I ALWAYS do a test off to the side after every bobbin change. Any problems usually show up there. Sometimes it's something as simple as unrolling some thread off the bobbin. Mine doesn't like it all the way full.

My machine doesn't like all the way full bobbins either. She also balks at the very end, so I usually know when I'm getting close to empty. Do you think it is because the surface is not quite flat? Maybe there's a slight hump in the thread pile? Out of curiosity I have tried to figure this out to no avail.

my bobbin goes good even to the end. My thread got wrapped somehow when I was putting it in so it was a operator error

really like this idea for the times I'm doing custom that needs the thread ends knotted and buried--I usually don't bother to bury unless it's for a show quilt--but this is a great idea there.

I noticed that happens sometimes when you run out of bobbin thread.

Yes, and pull the thread of the new bobbin at least 6" out of the case. I'm sure this has happened to all longarmer S at one time or another.