My bobbin stitch is too tight on my Juki DDL 8500-7, how can I fix this?

Do you have manual?

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwiA1ry50ozMAhVssYMKHQCcBUkQFggdMAA&url=http%3A%2F%2Fwww.juki.co.jp%2Findustrial_j%2Fdownload_j%2Fmanual_j%2Fddl8700b7%2Fmenu%2Fddl8700b7%2Fpdf%2Finstruction_eg.pdf&usg=AFQjCNELa9vBuXlODt-ff-b-EfwnMWW0dQ&cad=rja

sewing patternreview com

Perhaps contacting Juki support is a good place to pose your question.

Juki Sewing Machines

..

What thread are you using and what are you sewing? I'm assuming the machine is stitching correctly and it is just a tension issue. I would test each thread seperatly by hand and see if one thread is too tight or too loose. Thread on the bottom usually mean the top thread is too loose however it could by the bobbin is too tight. It could also indicate a slight timing issue or a burr on the hook. Is the thread shredding or getting damaged?

Does this look like your machine?

JUKI DDL 5530N Manuals

Is this a new machine or have you had the problem before

change needle the root of almost all problems!!!

perhaps you have the wrong needle or its not in the proper position?

Go to the website freemanuals.com They may have yours

I just bought the same machine and mine came with a photocopied manual. There is indeed a bobbin winder on the side, there's a flat section on the side of the bobbin winder closest to you, if you push that forward it connects a wheel attached to a bobbin spoke, to the belt that runs between the machine and the motor. To wind the bobbin, put the bobbin on sideways onto the axis of the wheel that is on the inside of the machine, and push the bobbin winder forward.

The DDL 8500. is a high quality, single needle, straight stitch, industrial machine. If it is still in a good condition and the present owner is prepared to guarantee it for at least 3 months, it is a good buy. Retail for app. $790.00 new.

Good luck

What bobbins do I use on a Juki DDL-8300