The top always seems to be perfect no matter what. And unless the tension is set to really tight or really loose, I notice zero difference in the bobbin. In other words, there is no chance of a perfect tension. Maybe perfect is unattainable, I just had higher hopes for a machine of this quality. I don’t want to ruin the excitement of having this great machine, and if it has to be this way I’ll survive. But no matter what fiddling I do, nothing really changes.