STITCHES GREAT ON TOP BOBBIN STITCHES ARE TOO TIGHT?

[Casual Quilter]

When I test my stitches on a scrap of bleached muslin on my quilt sandwich my top and bobbin stitches both look great on the sample.  But when I quilt on the actual quilt top, the top stitches are perfect and the bobbin stitches are too tight.  Any ideas?  My quilt sandwich is not too taunt.

Thanks for your help, it is appreciated.

[Cagey]

Your test sample has to be the same materials as the actual sandwich.  If not, you are not adjusting your tension for the actual environment you will encounter.  That is why it is a good idea to leave extra material on the borders so you can test your tension there.  Then move into the center of the quilt when your ready.

If on the real quilt sandwich the bobbin thread is winning the tension war, then you need to loosen your bottom tension or tighten your top tension. 

As I think the bobbin thread may be too tight from your post, try this link first; https://www.apqs.com/what-causes-railroad-tracks/

Here are a few other links explaining tension on APQS.

https://www.apqs.com/tension-troubles-on-your-quilting-machine-try-these-tricks/

https://www.apqs.com/tips-for-tension/

https://www.apqs.com/can-properly-adjust-tension/

Best of luck to you.

Cagey