Thread tension for FMQ?
 

I currently have three quilts that are in the quilting stage, all with FMQ. I have FMQed nicely before, with no problems, so I know it can be done:-) Last night I was pretty tired out and accidentally hit a basting pin with the needle. I think it was after that that the tension or something went wonky. Of course I changed the needle straight away, but I am still having trouble. The top thread is showing on the back no matter what I do. I rethreaded both the top thread and the bobbin. I cleaned the bobbin case. I have the feed dogs lowered, and the pressed foot lowered. My FMQ foot is instilled correctly too. And I have been playing with the tension up and down on a scrap sandwich with no results. So to experiment, I decided to raise the feed dogs and put in my walking foot instead... Now it runs perfect! But what's wrong with my FMQing? I would be so grateful for any ideas! I'm in a real jam here, help please! Thank you so much!!!

I would turn it off, wait a few minutes, and turn it back on. It may reset itself. If the top thread is messed up, then it is your bobbin tension or your bobbin. Good luck with it.

Timing being off would be my first thought after hitting a pin. That happened to a friend of mine.

I have a fully metal machine, with no computer parts in it. I don't think it can reset itself, but can the timing still be off, and if so, how do I fix it? I have a Singer 4423. Thank you for your help!

Yes, the timing can be off. Timing refers to the exact interaction between the needle and bobbin threads. Some machines are more sensitive to trauma than others but, in general, timing can be thrown off on any machine when a needle breaks while sewing or when there is a big thread jam.

Before taking it in for maintenance, I would check and re-check the new needle. It is quite common to insert a needle and not push it *all* the way up on the shaft. This often causes a timing problem. Also, try a needle from a different package (occasionally a bad batch of needles isn't caught at the factory) and/or a different size and type of needle. For example, if you have been using a microtex needle try a topstitch needle. If you have been using a size 80 needle, try a size 90. Needle type and size can subtly alter timing, so changing the type and/or size of needle might be enough to offset whatever timing problem might have been created by hitting the basting pin.

Last resort is to take it to a technician to re-time. I think there are a few Youtube videos that show how to re-time, but most of us would not be able to do it -- especially if the machine is different from whatever is on the video.

Also, use a magnifying glass in the bobbin area to see if you can spot any tiny piece of thread or lint that might be interfering with timing. Depending on your machine, you might be able to use unwaxed dental floss to "floss" between the upper tension discs (do this with needle up, as needle down closes the tension discs). This is a longshot, but also a possibility.

Just curious. Did any of the great suggestions above work?

The other day I was doing FMQ on a table runner. I was using 40 weight thread. I had two different threads for contrasting work-from two different manufacturers. I was using a 14 topstitch needle. I was using 50 weight, 3 ply cotton in the bobbin to match the backing. One thread stitched in beautifully but the second one had top stitches showing on the back of the runner. Don't understand that-both threads were 3 ply 40 weight. I did not reset anything and did not turn the machine off when rethreading from one to the other. I switched back and forth two or three times just to see if there was a 'me ' factor. The results continued to be the same. I hope laundering the finished piece will help.