Messy stretch stitches

[Lulu]

Can anyone please explain to me why this is happening?  It is a stretchy cotton jersey fabric (quite thin), with gutermann thread and a thread tension of 6, if that helps?

[Roger]

Needle... is it new, in the right way round and right for the fabric?

Reminds me of my 401... before I tweaked I had the needle in backwards... after almost taking the machine apart to check the timing.

[Ploshkin]

Is that a basic zig zag stitch?
If it is, it looks as though you might be stretching the fabric as its sewn, leading to uneven stitches.  You shouldn't be hanging on to the fabric and wrestling with it, just guiding it to keep the stitching going where you want it.  Try running some sample seams through the machine without touching the fabric at all.  You'll be surprised how straight it will sew without your help.

When you use zig zag for stretch fabrics you need to reduce the stitch width a lot so that you very nearly get a straight stitch but it is actually a flattish zig zag.  No matter how much you are itching to get on It's always best not to commit yourself to sewing on the actual garment until you have your stitch right on sample fabric.  This often takes several goes to get it all right with the different adjustments.  On a stretch fabric I would always do sample stitching in both directions as the fabric can behave quite differently each way.

[arrow]

Gütermann sew-all weight polyester? It should be the easiest to get the stitching perfect. Further trouble shooting: Tension setting; test sew with straight stitch on two layers of shirt weight woven cotton, then the stretchy stitch pattern. When balanced switch to the jersey fabric and make sure it's newly steam ironed. To get the threads to interlock just so on two layes of light weight fabric layers requires fine tuned tension. Make sure to match needle and thread size suitably. If you want the straightest line of stitches you might go for sharp point needle, but if you want the stitching to go between the treads in the knit you go for ball point tip or micro tex, the last two is generally recommended for jersey. For jersey it often helps to lower the presserfoot tension, but not all models have this function.

[Surest1tch]

Assuming that's a 100's thread I think I'd be inclined to try with a 120 or 150 weight thread and perhaps take some pressure off the foot.  Looking at the photo the thread looks a bit heavy for the fabric.

[Catllar]

Are you using a knit needle - or a stretch needle, come to that?

[Bogwoppit]

Hi Lulu. I find I have to do a lot of testing with jersey on my sewing machine to get it right. Much harder to get set up correctly than with woven fabric.  Use an offcut and test test test. I have to write down the setting so that I know which works best.