Sometimes tension can be the specific machine. I had one DSM that did really good except in one direction. I could go in about 330 deg and then in that one 30 deg triangle (would be like moving towards the 1 - 2 positions on a clock face with the needle at the center) , the tension would be bad and it would snap the thread quite often.
I've also done quilt a bit on several vintage machines, and found I had much less tension problems on straight stitch machines, maybe it is because of how the hook/timing need to be to catch the thread whether the needle is to the left or to the right of center. Though if you have a vintage machine that both the needle and the bobbin case swing, then that is not an issue.
You also may want to try different feet. Most of my vintage machines did much better with a hopping foot, but some did better with a floating foot.