Help with zig zag (on an applique) problems
 

I don't know why this is happening. I was using one machine and switched to another to avoid the problem but it still is happening - even on a completely different machine.
My zig zag I'm using to outline/adhere an applique is showing top thread on the bottom and bobbin thread on top. It's only happening on the edges, but it seems random. I have a satin piece of fabric adhered with pellon to a fairly heavy interfacing. I have tried changing the tension, the needle etc. Not sure what to do now. I will add pictures, but could use some advice asap. Hope someone has the answers :-(

I'm not sure, but it seems to me you need to tighten both bobbin and top tensions. I would use a testing sample of the same fabrics and thread to see if this helps.

The zigzag stitch is the one that tells you whether your tensions are adjusted properly. Imbalances that do not show up on a straight stitch will show up on a zigzag.

Edit: I also see that the issue is on the curve. Bobbin thread is pulled up on one side of the curve; top thread is pulled down on the other side of the curve. I am wondering if the thickness of your fabric/stabilizer combination plays into this....

On second thought, you need the gold thread to look perfect on the top, right? I think the solution is to loosen the top tension *slightly* and tighten the bobbin tension. That will allow the bobbin thread to consistently pull the top thread down, whether it is on an inside or outside curve. It doesn't matter if the top thread shows underneath.

Sorry for the rambling. Have not had enough coffee yet today.......

Are you sure the interfacing is the type meant for sewing? Some heavy ones are not.

Did you try cleaning the bobbin area and rethreading the machine? It sure looks like a tension problem though.

My Bernina did the same thing last week. I tried every tension setting I had and still got the thread difference. I called the Bernina shop and was told to use the same color in the bobbin and top. That worked. It only did this with the zig zag stitch.

Using the same thread in the top and bottom doesn't really solve the problem; it just hides it. However, if you don't want to spend the time trying to adjust the tensions, it is a quick fix.

With my Bernina, there is a hole in the "finger" of the bobbin case. When satin stitching, the instructions say to run the thread through the hole before inserting the bobbin case and bringing the thread up.

Be sure that before you start adjusting the tension, you mark where the original settings were so that you can return them after you have finished the project. A fine point Sharpie will work on the bobbin case to show where the screw was originally set.

I am with Tartan re using the same thread top and bottom. My machine does not like mismatched thread.

Good luck with it.

I had this same problem a couple of days ago, I will try using the same thread upper and lower thank you!!!!!!!