I had this problem yesterday during a quilting class. New thread in machine and it kept shredding. Had worked perfect the previous day. Changed needles and worked like a charm.

I had had shredding problems since around Thanksgiving. I met the owner of the company that makes my machine and he offered to come to my house to fix it! Do you think that machine would shred ONE THREAD? NOPE, Nada, NOTHING! (I was mortified! lol!) He DID however find a big glob of oily lint lurking in the bobbin raceway. Took him about 15 mins to find it. When I had had time to recuperate from the 4 days at the quilt show, I replaced the needle (had the wrong kind in there..mortified AGAIN! See a pattern here? lol) I tweeked the eye of the needle and VOILA! No shredding! Guess what I will be trying next time I have shredding problems? Hope you find your culprit...its a mystery you have to solve!

If you have checked the thread and needles then I would look at maybe for burr along every point that you lace it thru. I had a teeny, tiny one in the hammer hole; my hubby is a machinist by trade and is the one that caught it after hours of frustration on my part. The needles still might be the issue if they were stamped at same time might all have same issue, maybe try a different package of needles. I hope you get it remedied soon.

Your tension might be too tight.

I had this trouble with my Juki when I first got it. I tried EVERYTHING! It was soooo frustrating. The thing that finally made a difference for me was Sewer's Aide. I run a little line of it along the outside of the spool of thread before I put it on the machine. I think it keeps the friction down when the machine gets going really fast. I also use bobbin genies with prewound bobbins. It doesn't seem to matter what kind of thread I use when I use this "system." I hope you find a good "fix."

I have an Innova and am having a problem with thread shredding. I have a size 18 needle, and am using Glide thread. I have changed needles, re-threaded, checked needle eye position. Quite frustrating.

I had a tiny burr on my bobbin plate that was shredding my thread. I used an emery board to smooth it out.

It is immensely frustrating, and I had the same problem. Since I started setting my bobbin as Jamie Wallen shows in the video, I have not had any problems. And it works with all kinds of thread. I use Signature and King Tut, both behave with the bobbin tension loose and balanced with the top thread. I also skip a thread guide.

I had a problem with thread breaking and finally found out that I had a small burr on the foot itself. The thread kept rubbing against the burr until it snapped. I used my finger nail file to file down the burr and solve my problem.

There are two Innova groups on groups.yahoo.com that may be helpful. I have seen it mentioned there that one of the thread guides can develop a burr and may need to be smoothed out or even replaced. Also, that the check spring can need replacement. Several people keep extra check springs and thread guides on hand. If you can find an old nylon hose, you can try running a section of it through the thread guides to see if it catches on anything. Also check the bobbin case, bobbin case assembly, and needle hole for burrs (try running a finger over the areas).