Bad stitch with thicker thread

[Lacoedo]

Hi everyone,

I have a Brother NV800 Embroidery machine. I've been doing some topstitch experiments and run into some issues.

As you can see in the attached photo, the original test (outlined in blue) with a 100/2 Polyester thread looks good.

But when I used a 30 Thickness Cotton embroidery thread, I'm getting these weird results (outlined in red).

The stitch width for both examples is 2mm. I tried adjusting the sewing speed to minimum for cotton, and even adjusted the tension, to no avail. The machine's instructions say I can't use a thread of 20 or thicker.

I'm using the same thread for topstitch and bobbin.

 

Any advice?

 

Thanks!

[Lacoedo]

Okay, so upping the Tension all the way up to 5 solved the problem.

Sorry for the spam everyone!