Originally Posted by
steihy
I guess Tammi got all the problems she needs for this session, but this thread (sic) in itself has turned out to be a great tension tutorial. Let's keep it up.
I know that I fiddled about a lot, but didn't really make progress until I understood the stitch forming process. It's easier to relate to the different problems and suggested solutions once you understand why there needs to be tension to snug up the stitch in the first place. Every machine manual has the usual graphics of the under-, over- or balanced stitch, but they don't really explain what's going on. Nor do they explain the need for all the big movements and the big loops in the upper thread path. What goes on under the hood is simply magic, but once you understand it the fear of working on it disappears.
Showing an animation or good pictures, would be a good start. That's also a good opportunity to show that, allthough the needle thread takes abuse and does all the work in the making, the upper and lower threads form identical parts from there on, and share the load equally for the rest of the (balanced) seam's life.
Well, maybe not that critical in quilts, I don't know. I keep forgetting that this a quilting forum, and I'm only in it for the machines.
On the more specific level: Anything that happens every once in a while, or at the odd stitch, is not a tension adjustment issue.
It has been discussed, and I agree, that spool yanking is underrated as a problem. Upstream of several friction points and disks, it takes very little force change on the spool to create significant changes at the needle, enough to tighten up the loop and miss the hook I guess. Although there are solutions as discussed, I think the modern way with the fixed, horizontal spool is an improvement. You can find this solution on some pretty old industrials, so it's not complete heresy.
I don't know if snags and stutters are as critical down below, but I am Catholic about bobbin condition. Every time I load one in the casing, I test for tension and evenness by pulling thread slowly off the bobbin, and feeling it. Unless the thread is full of knots it should come off in a completely even and smooth manner, no jerks or ticks. I guess different contact areas for different systems - horisontal of vertical - but burrs and nicks, dents and warps, will affect the action. I know some people are fairly religious about bobbin pedigree, and I don't know enough to argue, but personally I don't feel bad about replacing a tired metal one with a fresh plastic substitute. You don't have to worry about a plastic one being slightly warped - it's good or broken. I know for a fact that my 201 behaves much better after I replaced the original bobbins that came with it.
Good luck, Tammi
PS: Now I see that Miriam said most of this already, not needing so many words. Oh, well.
You bring up a good point. I hadn't planned on covering how a machine makes a stitch - that was planned for the maintenance class I'm giving the following week for a smaller subset of these gals - but it really is key to understanding a lot about tension. There's a good chance the day I learned that was when tension started to fall into place for me too.
I'll take a 201 with me. I find without the retaining piece and the dogs removed that it's one of the easiest mechanisms to show a stitch being formed. That's why I used it when I made the YouTube video about how timing works (essentially the same thing that we're talking about here.)
When I started hanging out here, I didn't quilt either. I only started quilting in 2013. The machines did and still do come first for me and I suspect that's true for a few of us here.
Tension is critical in quilting - if it's not right fabric is damaged or seams gap or things ravel. Additionally, the way we do surface design has changed. We don't run tensions nearly as tight as we used to, poly for surface design is being "requested" by museums because cotton is rotting and the design is lost, poly isn't "stronger" than cotton anymore (in some cases) but as most things, it's taking time for that to filter through the industry.
I do like the horizontal pins, or at least pins that are more suited for the threads most commonly available these days. That's why I advocate for thread stands. In fact, I even built a thread stand for my embroidery machine to take the thread off the machine - even though it has a proper horizontal pin for the thread I use. That reminds me, I must bring a thread stand on Monday. And a roll of toilet paper.
Bobbin thread delivery is as important (or nearly so) as the upper thread delivery. As you mentioned, it has to be balanced. If it speeds off because of a lack of tension, the stitch will lock above the layers, or worse. If it's tight, it will make the stitch lock below the layers, or cause breakage or other sorts of issues like eyelashing in FMQ.
I'm not a puritan when it comes to bobbins. I believe that if it works right in the machine, I use it. I will take a known good plastic bobbin before a damaged metal one any day. Any time one of my bobbins bounces off the floor, it's examined for integrity or tossed (some of the plastics I have are rewound disposables. Those I just toss if they've hit the ground because I usually find them by stepping on them. *sigh*). The only place I AM a stickler is no metal bobbins in plastic cases. They wear the plastic out. I've seen bobbin cases with all sorts of wear from this.
It does bear noting that in some cases there's enough of a weight change here to require a bobbin tension adjustment too. This might be why some people say that plastic bobbins don't work as well in their vintage machines.
Originally Posted by
ManiacQuilter2
I think a lot of quilters think they have their tension right but the true test is doing FMQing.
I agree. A balanced stitch isn't actually the whole story, so even when the stitch is balanced it can often be improved. FMQ introduces a whole other set of factors - needle deflection, timing of the movement of the sandwich and then when you get into frame quilting even having the sandwich too tight or too loose or too high or too low will cause issues like skipped stitches and "tension" problems.