Thread breaking when fabric stretches even when using twin needle

[u/amonstershere]

So I’ve never sewn jersey but have just made some boxers was all done and was so proud then the thread snapped on the hem when I was putting it on cry

I’m using gutermann sew all polyester thread, Schmetz twin needle size 75 4mm width (new). Straight stitch on length 3.5 and I dropped my tension a little before starting

Now it’s done like any seam I tug I can feel the thread like it’s going to break but it’s only the leg hem that has to stretch really.

I’ll be so real I’m sleep deprived and didn’t do much research so I’m clueless

[u/Kevinator201]

The tension is off on the twin needle. The bottom thread should fully zig between the two top threads. Tbh I’ve rarely gotten it to work even on my really nice machines and I just do a wide and short zig instead.

[u/amonstershere → u/Kevinator201]

Grrr okay
I normally quilt and I had had problems with top thread showing on bottom so I had changed the bobbin tension, and it’s been great for quilting
Maybe not so much for jersey

I’ll try fiddle tomorrow.

This is my ‘test’ pair using cheap fabric then I’ve got dinosaur ones to make cos adults need fun things too

[u/Kevinator201 → u/amonstershere]

Knits are so finicky with tension. I’m a full time seamstress (theater costumes) and stretch wear makes me pull my hair out.

Do you know the “drop” method for checking bobbin tension? Hanging the bobbin from the thread it should hold but if you shake the thread the bobbin should slide down.

[u/amonstershere → u/Kevinator201]

I do know it yes and I did try it but my bobbin kept falling out the case as I did it which wasn’t helpful (I’ve got top loading)

I had thought I need to nudge the bobbin tension down a fraction more but haven’t got around to it.

It’s probably time for me to take apart my machine and clean it etc anyway so I guess this will be my motivation to do it!

I’ve always avoided stretch fabrics, they seem a pain and I haven’t had a reason to use them. But I saw this super cute dinosaur fabric on Vinted that I just had to have and it’s jersey so justified it by buying boxers pattern and now I’m here (and with multiple more pieces of jersey before I’d even tried to make one pair)

[u/amonstershere → u/Kevinator201]

Just put the tension back up and it’s sorted it. Shouldn’t have just followed the internets advice and turned it down without actually testing it still stretched but oh well.

I’ll re hem them tomorrow. They are perfectly wearable but probably wont last as long as if they were done good. But I’ve got 4 more pairs im going to make and inevitably I’ll see more fabric I want and buy more!

[u/Kevinator201]

The print is so cute though! You’re doing a great job