mkc

Something to try - repeat the test with a typical quilting cotton instead of linen. If that looks ok, try a lightweight fusible on the back of the linen and repeat the test.

Linen has a looser weave and a tendency to stretch. It could be that the fabric stretching during stitching and relaxing back into place afterwards is what's making the stitches go more "wonky" than expected.

That said, machines capable of decorative stitches will always have a slight angle to them. If straight stitches are important, a straight stitch machine will have the advantage.

Juki's TL series might be worth considering.

quiltedsunshine

A finer weave fabric will produce a straighter stitch. A smaller stitch length will produce a straighter stitch. And if you tighten both the top and bottom tensions a little, that will help produce a straighter stitch.

eliza422

Thanks for the link - that was very informative!

cashs_mom

I was thinking the same about the linen. Linen tends to be a looser weave that might skew the stitchs.

I also agree with the Juki TL 2010 or the 2200 QVP MIni (same machine, different accessory package). Its a good straight stitch machine.

Onebat

Argh sorry - I keep typing answers and then the token expires and they go pouf!
@eliza422 That's really good to know - I will chekc the Juki out.
@DawnFurlong Glad I'm not the only one!
@bearisgray Straight stitching *is* hard! But I've worked and worked on my technique and am happy with the actual straightness of the lines now - it's just the stitches themselves!
@sewingpup Hmm - there is a Viking MegaQuilter on Ebay for £500 right now - I'm tempted to make them an offer! I have another Viking I could get rid of..
@osewme That's *very* interesting. I love my Janome in every other respect - just the blimming stitch straightness.
@JanieW Thank you, that's so useful - I will do those tests. I wouldn't have a problem with skewed stitches if they were all skewed and regular, but it's quite random.

Onebat

@mkc and @cashs_mom - so interesting about the properties of linen! I will definitely try now with another fabric and report back.
I also realised that the tension is wrong on the darker stitches in the example photo. I will try again with it set better and also follow your suggestion of tighttening the tension @quiltedsunshine - good plan.

More testing to do, and a service I think - and I'll keep my eyes peeled for a Juki TL 2010 in the meantime.

Thanks so much everyone, I really appreciate the suggestions.

illinois

Do you have a single hole plate on your machine? Sometimes that will be what helps keep stitches straight. Just remember to change back to the other one when you want to do decorative stitches!

SuzSLO

Have you tried a test by sewing on paper without thread? How about a smaller needle?

Lyncat

If you want a perfect straight stitch, get a vintage straight stitch machine (before 1960). You’ll be amazed.

mkc

FYI, the 2200 QVP Mini was discontinued fairly quickly and had been replaced with the 18QVP (which offers improved lighting and adds a micro lift adjustment for the presser foot, but is otherwise a 2010).

The 2020PE is a silver-finished 2010 with several additional feet (mostly hopping feet for the US market; garment making for the Japanese market).