Sewing machine troubleshooting - bobbin thread bunching up

[squidipa]

forstraight stitch i use 3 for tention on my machine i have 1-6 as a tension option. make sure you ahve wound the cotton onto the bobbin tightly. make sure you are putting the bobbin in corectly and its not bouncing around. Also check the bobbin is threaded correctly and stitch lenght is correct. Check you have the right settings and presser foot for the stitch u are doing. Also the bobin will normally go one way and the cotton will thread threw or catch on some thing check the manual or correct bobbin placement and threading.

[~Raven~]

Make sure your bobbin is turning in the right direction. ie mine turns counter-clockwise and I had similar issues when I put it in the wrong way!
(I have a Janome so it might be different to yours in that respect )

[Indadhanu]

Yep, have the bobbin in the right way

It's odd... one minute it'll be working and then the next it won't

[squidipa]

Yep, have the bobbin in the right way

It's odd... one minute it'll be working and then the next it won't

what fabric u sewing?

[Indadhanu]

Well first I replaced the hook amd loop in Jazzys nappies, it worked fine. Then I started to finish off some pads, sewing PUL at the moment, and it went all tempermental :S

[squidipa]

Well first I replaced the hook amd loop in Jazzys nappies, it worked fine. Then I started to finish off some pads, sewing PUL at the moment, and it went all tempermental :S

i started sewing pull the other day and i found i needed to have a long stitch and a extra loose tension other wize it was to tight. try that? eithor way i can prolly check it out sometime for ya

[Arcadia]

PUL is notorious for this! I found I had to get a walking foot or teflon foot otherwise I had this issue. I think its because the fabric is shiny on one side and a bit rougher on the other.
ETA: What needle are you using? I found I could sew PUL more successfully with a really big needle - like a leather needle.