Threads and Stitch Length

I have a couple of quilts that the seams are coming undone on, I came to the conclusion that its because my stitches are too wide/long and so it makes it easier for them to break and then bigger seam sections become opened. Most of my stuff is done with cotton thread, is poly stronger, does poly cut fabric, etc etc. So I got to thinking why not have a chat about it here, so............

1) What size stitch do you use when sewing and why? (can you provide a photo too?)

and

2) What type of thread do you use, cotton or poly? Why?

I generally use cotton, as IMHO, poly is more likely to cut into the fabric. Once in a while I use cotton wrapped poly. I keep my thread in drawers, to avoid light damage. I get rid of weakened thread. When I started sewing quilts, I was told that 2.5 was the correct stitch length, or 2.2 for paper piecing. Now I hear 2.2 and 2.0. 2.2 is the automatic on my Janome. I have never had a problem with quilts coming undone. I have found that the brands of thread that I used in my youth tend to shred, so I tossed them. Mostly, I use Signature, with a few others from time to time.

Mine is set to 2.4. Too much lower and the stitches become to tight! I use cotton and poly wrapped cotton.

My machine defaults to 2.5, also. (click to biggify)

I am not one of those who insist upon 100% cotton thread. I figure if good old Coats & Clark is good enough to keep my trousers from falling apart off my backside, it's good enough to hold a quilt together.

As for polyester thread 'cutting' the quilt fabric? Again... it doesn't cut my trousers, even when in a high-stress area (that backside again), so for a quilt that doesn't have stress on the seams I can't see that it would be an issue.

I tried several different brands, but settled on Gutermann, 100% polyester, 2.5. I keep mine in a drawer. I've heard that thread should be protected from light, don't know if that is true.

Mine looks to be the same default size as Tracy's....as best I can tell. I do make the stitches longer when I am quilting, I feel it looks better with the thickness. I usually go to a length of 3 for quilting. I use polyester thread. I use Glide from FilTec Bobbin Central. I love the colors and the tiny bit of sheen the thread has. Beautiful for appliqueing. It is also what I use on the longarm and I find it easier to just use the same stuff all around. There is so much polyester thread out there I feel like it can't be bad or it wouldn't sell. I agree with Tracy about the quilts not usually being under stress and so shouldn't be a problem.

One thing I have noticed on my machine, I have to be careful when starting because the feed dogs seem to pull the fabric through before the stitching starts and if I am not careful my stitches don't go all the way to the edge and may not get secured by a cross seam and start coming undone. So I try to keep a watchful eye on that.

Another area of concern is when ripping stitches. If you are taking things apart it is easy to pull a side seam open a bit when you are working on the ripping. So keep an eye on all your seam intersections and fix any that pull apart.

Thanks for the metric picture Tracey, I will be checking mine this afternoon I hope, if the rain will come and then DH will stop squalling for me to come outside and stand there while he does this or that.

I appreciate everyones comments and input, its nice to be able to ask and discuss stuff. Im not really sure why some of my seams have popped on quilts, its on multiples, not just one, I checked my seam allowances and apart from one or two they are all 1/4".

I was also interested in the thread types, I like cotton but I find now days so much of it is poorer quality and it sheds lint and burrs up in the needles adn breaks etc. I have both cotton and poly cotton. I havent noticed a difference between the stitching but Im wondering if perhaps the cheaper cotton might have broken in a seam on the quilt? No idea. I like gutterman and have tried some aurifil that was a gift, it seemed nice. I have some of the connecting threads stuff, lovely colour selection, I seem to find the right shade easily. I got a couple of their colour themed packs as a bday present last year from MIL and they never seem to burr or break, I like them.

FB I have wondered the same thing, if poly doesnt cut into our clothing that is often made from flimsier fabric than quilting cotton then why would it cut into a quilt that is more static and not worked as hard as shorts and tops, underwear etc etc

When you say your machines have default settings, do you mean computerised ones? I had an old elna and now a basic entry model brother, nothing electronic on it and you have to select and set the length and width. I am constantly changing them for applique and straight sewing. I have a piece of cardboard I stitched different size stitches onto then marked what the corresponding machine setting was so I work like that.

I have 4 cardboard photo boxes I have had for years I keep my threads in,

orange/pink/red/purples
blues/greys
greens
neutrals/black/white

They stack neatly on my shelf, I dont own oodles of threads so what I have fits nicely.

I know that stitch width when changed whilst straight sewing alters the position of the needle and is good for scant seams etc. I think until I changed last year that I used to stitch with a length of 3 or 3.5 set, what my mum had taught me yrs ago, I have to say, its certainly easier to unpick - seam rip with the shorter length

An "expert" on TV said that one should not keep threads over 3 years.  I have always protected my thread from light damage, which I do know for sure is real, so I wondered about my older threads.  I had a special box of expensive variegated threads that  I had been using sparingly for over 20 years.  All but one passed my tensile strength test.  A friend did a number of precise tests on a variety of threads  at her quilt store.  Aurofil (sp) came in first overall, with Gutermann and several others not far behind.  Coats and Clark and Star were significantly lower performers.  I know that I bought a spool of Star thread and one of Coats and Clark because they were exactly the colors I wanted.  I ended by tossing them.  They broke much too easily and shed lint all over my machine in copious amounts.  I have never seen Madera on sale in a quilt store.

I presume poly thread cuts into fabric because it does a number on my fingers.