AlvaStitcher

I have a Singer 403 machine and the bobbin occasionally locks up and jams thread down in hole. It sews along just fine and then will jam up. My repairman looked it over and said he could not get it to jam. It happens when I am starting and stopping frequently while sewing. Hope I am making sense here. Any suggestions on what can be the problem? I am using a bobbin 66.

Mickey2

Make sure the bobbin goes in the correct way, and make sure the thread doesn't get dragged down the needle hole on the first stitches of a seam. That's all I can think of at the moment.

Cari-in-Oly

Take it back to your repairman. Have him remove the bobbin case and clean out the track it rides in with a toothpick or a pin. You'd be amazed at what looks like metal is actually felted lint under the bobbin case, it causes any number of intermittent issues like you're having.

Cari

bkay

I had the same problem with my 401. Cari suggested cleaning, but I thought I had already cleaned it sufficiently. I saw this video and tried again. It really helped. You won't believe what you get out of there.

bkay

Edit: If it jams as you are starting, that's usually because you don't hold the threads as you hit the pedal.

Mickey2

Cleaning and oiling can solve a lot of diffuse issues. Go over the manitanance section in the manual, and videos like the one bkay links to are very good help too. I often go over a machine from one end to another several times, especially a newly required one. Spend some time on it. I use cotton rags, microfiber cloths, heaps cotton swabs, and even scrape out grooves and corners with tooth picks.

AlvaStitcher

Thank you for the replies. I will try cleaning it out again or take back in to the repairman.

Quilterman

If you have bought any new 66 bobbins they are made in China and the quality control is bad. If you buy 10 you
will probably throw 3 away. The diameters on some are too large and will cause the bobbin to drag. You will have
an intermittent problem when using these. Take every bobbin you buy and put it in the bobbin case and move it
around and spin it by hand to see if it is loose. If it is tight throw it away. I have had this problem mostly with the
new metal bobbins not the plastic ones.

Cari-in-Oly

This is a very good suggestion. I'm used to thinking about this when it comes to 15 class bobbins but it's been a long time since I needed any 66 bobbins so it doesn't always come to mind.

Cari

Mickey2

How are you doing AlvaStitcher? I don't know if you have had a chance to do anything to your machine yet, but like metioned, brand new bobbins can act up. With 66 bobbins the probem has mostly been not going on the winder properly, the inside has been finished off too roughly to slide on at all in some cases. The have all worked fine in the machine, nicely polished and with an accurate fitting in the bobbin case.

bkay

It could be the bobbin, but I have what appear to be vintage bobbins (at least I didn't buy them) and have had that problem. The way I would describe it is that top thread repeatedly wraps around the bobbin case and somehow appears to get hung on something under the feed dogs. It locks up the machine with your fabric under the presser foot. You have to cut the thread to get your fabric out and by then you can't tell what it's hung up on. It happens in the middle of a seam, not at the beginning.

I was ready to switch machines until I did the cleaning as shown in this video, which is the same one as referenced above. It's only happened once since then.

bkay

This is what I got out of the bobbin area after what I thought was already clean.
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