what is wrong with my sewing machine??

So I used with no troubles a few days ago...today i had to change to hot pink coloured thread, and the bobbin as well.
And now it just won't sew!! I'm not really sure what is happening...but it seems like the bobbin thread is not being picked up with each stitch, and it just ends up in a big messy knot, then pulls the top thread down and starts pulling the fabric down to the depths below... I've taken the bobbin out 5 or 6 times, put it back in the case again and back into the machine but it still won't work properly :wall:
The last time I tested it it wasn't sewing the top thread either, it just seemed to go nowhere, and the bobbin thread ended up in a mess. The machine (a Bernina) is probably about 3 years old and hasn't been serviced :redface: but up until now hasn't been used all that often, and I've never had any problems with it.
Any of the sewing stores in this area only deal with Janome's so I don't know if they'd be able to service a Bernina as well?

Mine was doing this the other day too, with no explanation. I re-threaded the bobbin about a million times, and changed bobbin thread more than once, and even took the plate off to clean around the bobbin area. And then, even though it was a bobbin problem, what ended up working was un-threading, refilling the bobbin so it was nice and full, and then re-threading from scratch.

Changing the needle may also help (???) depending how long ago you last changed it.

Ring around the local sewing shops, see if anyone will do it. If your machine's not under warranty or anything, it shouldn't be an issue.

Generally I find that if that's happening then it could be a couple of things.

1. Stitch length - too long?
2. Tension - too much?
3. Oil - are you oiling it before each use?

If you still have the user guide, it should have the pre-use checks to do, and some of the trouble-shooting in these instances.

my old one did that bunching up thing of thread when the feet? (i dont think thats the right word.) wouldnt move....oh man..sorry im not explaining it well..

like you know those things on the bottom that make the material move as you sew, well are they moving and is it moving the fabric? if not it will keep sewing in the same spot and make a big knot.

hope you work it out soon whats wrong with it.

Stitch length/tension haven't been changed. Oil...is it supposed to be done before each use? :hide: I had a look in the troubleshooting section of the manual and it wasn't very helpful. Will have a look at the 'before use' section though.
The bobbin is nearly empty so I might have to undo it and fill it from scratch. The needle still seems nice and sharp, it's not having any trouble going through fabric. I don't even know if I have a spare one..lol.
Thanks girls, just when I thought I had some time to sit down and sew it does this to me!

SS - different threads and materials need different tensions :) It really is trial and error to become a good seamstress :)

Different fabrics also need different needles. The needle can seem sharp, but after a long time being used it might be "expired" with an issue you can't even see - even like being bent so slightly that you can't tell. If you don't have a spare, take it out and put it back in - might help a little.

well, I pulled it apart and gave it a good clean, and some oil. there was a fair bit of dust/fluff in it so maybe that was the problem. it's going alright now...*goes and signs up for sewing machine abusers anon* :hide:

The last time that happened to me DD was "helping with the machine & after I wound a new bobbin I didn't rethread it properly. I spent hours trying to work out what was wrong & cracked it big time ony to figure it out the next day when I looked at it