Sewing Machine thread breaking - solutions?
 

Writing this for my friend. She has a Pfaff Creative Expressions 4.0 that is well taken care of. Serviced regularly, not over worked, cleaned often.
Twice now, on a sewing day, her machine has repeatedly broken the top thread after 2-4 inches of sewing. Cleaned, re-threaded, bobbin re-seated, changes of thread, needle, bobbin etc.
Changing one thing at a time, tried all the above listed.
Still breaking thread after a few inches.
She will be sewing along, at a slow/reasonable rate of speed, the machine makes a funny clunk sound and the thread breaks.

We can't solve this!

Any thoughts?

All ideas appreciated!

I wish I knew and could tell you, but I have no idea what this could be. I'd say with that clunk noise, it needs to see the Pfaff mechanic.

On the throat plate are there burr's on the hole that the needle goes through? If this is the problem you can use a metal finger nail to smooth it out.

I was thinking of a burr as a possible cause, and that's why we changed needle and bobbin both. I'll have her check the hole through the plate. We hadn't thought of that.

What thread is she using? I was having a similar problem and it turned out the thread was catching on the end of the spool, and another time I was using the little small piece that holds the thread on the spindle that was the wrong one and the thread caught on it too. Also, what is the thread spool like? There are two styles, one where the thread is wound on the spool layer after layer, and the other is it's kind of twisted on - that's not a good description - but how it comes off the spool does matter. Is her thread laying down or standing up? Maybe she needs a thread holder. I have to use one with my featherweight when using a larger spool of thread. It lifts the thread high enough and it doesn't drag on the machine.

I agree with quiltingcandy. I had this happened. Thought I had a bad spool, etc.
Using the thread holder and spool cap was the fix.

I'm not sure a burr would cause a clunking noise, which is the symptom you mentioned that concerns me the most. I'd take it in.

I've got this problem on the occasion with my machine, though not the one she has.

I found out that my machine (brand new I might add, a mini-machine, too) is very, VERY picky with the kind of thread I use. I was trying to use polyester/cotton thread and every time, the machine would clunk after a few stitches and the top thread would break. I don't know how many times I re-thread the machine, take out the bobbin, even rewound the bobbin, I still had that issue. I changed out to another thread, no more issues.

100% cotton through my machine, no clunks and no breaking of thread. I would also suggest that she figure out just how old that thread is, my older Dressmaker doesn't like older thread, if I'm sewing and I break the thread too many times, I swap out the spool with a newer one and it stops.

I was going to suggest checking the spool of thread for possible bad thread, until I read that the machine is making funny noises, so agree with the others. May need a trip to the service man.