Here's a tip: use dental floss to clean the top tension disc....just run it thru as you would thread, but with a bit more tension....

Thank you for the information. I have used prewound bobbins and have less trouble with them. The top tension is a spring between two metal disc. Took apart cleaned and gave it a buffing cloth run over that the guy in stover told me to use but no luck.

I love the machine when I use white 50/4 or 50/3 poly cotton thread and the prewound bobbins. But white gets boring on my colorful quilts. I have tried threading and retreading it but still have extra string on bottom. Guess I will see if a regular sewing machine person could take a look at it.

you can't buy the bobbins in different colors?? I wind my own bobbins use a sample quilt and just keep changing the tension of the top until it gets better don't be afraid to change it

I have wound my own bobbins but it still had some backlashing on bottom. I haven't found any prewound in lots of colors. But maybe I don't know where to exactly look online. I tried prewound super bobs but they did the same thing. I guess I need to see if I can't keep playing with it and hopefully I find the right tension.

Try here for prewound bobbins in all colors. Glide thread and bobbins are the best I've found for machine quilting.

http://www.bobbincentral.com/bobbins.html

TBumgarn, you probably should invest in the Magic Genie disks. It almost sounds like your little springy-thing inside the bobbin case is not giving you enough tension.

Here's a link to a video by Jamie Wallen, that specifically deals with tension issues. The very FIRST thing he talks about is the bobbin case.
https://www.youtube.com/watch?v=Q1mRhcquZTM

Any time I have issues with my system, I hop over to YouTube and look for "Jamie Wallen [my issue]". Jamie has done so many videos on YouTube, I have never had to call a tech to work on my system.

Hope this helps!!

Jamie Wallen really does a great job on the tension well he also has one on oiling in the bobbin area he is very easy to get

I've used the Magic Genie washers for years. Love them!

Is the tension too tight on your leaders....is it like a trampoline? Should be loose as hand quilting......