Borther ce4000

Question

I just bought this machine and have tried, tried again to get the stitch to be even. The bottom thread is just to loose. I have rethreaded several times thinking I was doing it wrong. Rethreaded the bobbin and inserted it the correct way and even backwards nothing works. And yes I have adjusted the tension k**b from 6 to 1 in small increments and still no luck

Help, I am in the misddle of a project when my old machine finally broke. I am sewing duck cloth and using dual duty thread.