Bad stitching on back

Hi

I have a barudan 4-head machine.

I am currently using 3 of the heads on a sample logo embroidery. (1 remaining head is under maintenance/repair)

  • 2 of the heads will embroid as shown in the picture. this is the back of the logo. the yellow thread.
  • 1 heads will embroid fine.

What could be the issue with the 2 heads? I can safely assume the design is fine since the 1 head is fine.

Location: 
United States
Robert Young's picture

Bird Nesting is the common name for thisl

copying from Coleman & Company website (https://colmanandcompany.com/blog/2013/03/embroidery-birdnesting-tips/) :

"Incorrectly threaded upper thread. Check all thread guides. On some home sewing machines birdnesting happens when the line jumps out of the take up lever, which severely reduces tension on the thread, allowing it to be pulled to the bottom of the hoop easily. Unthreaded take-up levers will always cause birdnesting.

A tight bobbin tension, together with highly loose needle thread tension, can cause birdnesting."

Modern Embroidery Designer
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