Bobbin tension on Viking 350 Sewing Machine

Viking bobbin case tension adjustment:
When the bobbin runs out, sometimes it bends the bobbin case tension spring. Then tension is too light. Take the bobbin case out of the machine. Tie the loose bobbin thread to the Designer 1 needle plate. Insert the bobbin in the bobbin case. Here’s the tricky part set the bobbin case on the table as if it’s in the machine (Bobbin is visible and sitting horizontal to table top) threaded as if sewing and loose end tied to needle plate (that is removed from the machine). Lift the bobbin case off the table rotate it so that the flat side of the bobbin are vertical to the table and no longer horizontal. Have the bobbin case oriented so that the thread coming out of the bobbin case sprint (slot area where it is put for sewing) is at the top. Lift it high enough that the needle plate is lifted from the table. It should not release thread unless you shake it gently and then a very small amount of thread. The needle plate is the exact weight resistance your bobbin case should have on the thread.