I was blonde-headed when I was a kid, so maybe I’m just having a blonde moment with this thread/humidity idea, but I’m getting tired of sticking my feeler gauges into these machines. There’s just got to be another reason for some of the thread messes besides bobbin case clearance.

The wife is usually mad enough when it happens that she should be able to remember to make a log entry for me. I wonder if I should ask her to log how she was holding her mouth when it happened? If I do, and she does, I may have to edit the data just a tad before I can share it with anyone.....

CD in Oklahoma

Hmm,now we need an ESD ( Electro static discharge) bench and wrist straps ( proper grounding procedures) and have someone run one of these machine for a while.... I am only half joking I come from interior Alaska where the continued way sub zero temps result in relative humidity in the single digits and we can draw an arc about an inch long from just trying to reach the light switch.... and one of them fuzzy motel blankets will light up a room when you try to make the bed!

I actually think it IS tension related. Your tweaking with the alternate and alternate alternate threading is changing pre-tension - the tension inflicted on the thread before the tensioner itself - and post tensioner tension. Every guide the thread goes through affects the tension on the thread too. Tension is not just the tensioner. That finger that the thread is wrapping around in the other thread is built a little differently on my 411G but the only way a loop could get there is by not being controlled correctly - that implies a tension failure of some sort. I'm trying to think of another model of machine that has that finger in the inside part of the hook race and coming up blank. Maybe that's the slant connection.

Some Long Arms and other industrial machines have more than one tensioner because really high tension on one tensioner isn't the same as moderate on two tensioners. My long arm uses guides to apply the pre-tension to keep tension sane on some threads instead of that second tensioner. This is also something I played with while setting up a 503 to chainstitch. <- see? borderline relevant to the conversation. ;) Tension at 7 - 7.5 on the dial made a nice chain until the thread snapped. Lowering the tension to about 3.5 and adding drag elsewhere (post tension in this case) created a beautiful chain.

Embroidery machines, especially with the use of poly thread - because it's elastic and stretches and shrinks while sewing - seem to benefit from a little extra drag before the tensioner and I truly think pre-tension would resolve a lot of the grief people have with embroidery machine "isms" - sudden nesting, loops on top, sudden changes in tension, etc. They also benefit from the thread being on a spool stand and placed a fair ways from the machine so the thread has time to "relax" and unwind before delivering the twists and such to the needle. These are all similar symptoms to what we're talking about here.

Tension will be affected to some degree by the physical change in the thread.

LOL! Joe! That's because you basically had an entire spool treated with DIY "sewer's aid". :) It would never have occured to me to use that thread. I've had similar spools in cabinets and cases and I always throw them out immediately when I get the machine on the bench.

As for static, potentially. Maybe it causes drag, like when you pull a balloon across your hair. The sudden release could also do weird things. I do know that now that my studio is always between 37 and 45% humidity, I don't have the weird gremlins I did in the dead of winter.

In response to one of your earlier comments, you've mentioned a bunch of times that you sew slowly. A lot of problems aren't as noticeable if you sew slower. It's one of the main things we tell people doing FMQ and frame quilting - if you're getting "X" symptom, try slowing down and see if it stops.


I really don't think it's the clearance. You said it's never changed. Unless the mechanism is able to vibrate in or out while in use, it shouldn't be it.

LOL! I've never managed the 1" arc, but the blankets thing I've done! :) And the defying gravity with the hair part that goes with it.

I don’t think that constant tension is causing the problem, but rather a sudden increase in tension for a short period of time. That brief period of time that the loop is normally released from the hook to form the stitch. If so, it would appear that we may have a “thread flow” problem up top more than a thread tension problem. I think that the thread gets wrapped around the finger in the bottom when the upper thread loop makes a second lap around on the hook. Maybe a result more than a cause.

An increase or decrease of constant pre-tension should only effect how the upper tension assembly needs to be adjusted in order to form a proper stitch. Thread guide drag should remain constant until you add or subtract one. By adding thread guides as TnT has suggested and Tate has expanded on, might be doing more to effect thread travel and thread control rather than thread tension. It still may have a lot to do with thread twisting, which thread moisture may play a significant part.

The problem is, when the event occurs, the operator’s eyes are usually on the needle area and not watching what’s going on up top. If twisted thread not moving through a thread guide or the tension assembly causes the loop to not release from the hook, the second lap around the hook will jerk the twist past whatever it was hung up on and no longer be there after the event.

A similar event is when the thread gets caught in the stow slit on the old spools, except in that case, the hook can’t jerk the obstruction loose, so the thread breaks instead. I still think that the flow of the thread up top is our culprit, and that the humidity in the air and moisture in the thread has something to do with it. Even the change in thread manufacturing processes over the years could be complicating the diagnosis by some thread acting one way on these old machines, and other thread acting differently, depending on when and by whom it was made.

CD in Oklahoma

I agree that the threads can be making a difference. The thing about pre-tension or post tension though is that if the main tensioner is not touched but the pre-tension is - i.e. wrapping twice around something - something I see some LA'ers do, changing the thread path to make the thread change directions like Tate's doing, etc - the overall tension has changed. Like you said, an increase or decrease in pretension will affect how the main tensioner has to be set. If it's not set differently, then the overall is an gain or loss of tension.

I'm more referring to the changes that are made in an effort to re-mediate the problem. The sudden changes are something that may be absorbed by the pre or post tension and hence why the problem seems to go away. If it's a twist doing it, perhaps that extra pre-tension is enough to sort it before it gets to somewhere it can snag. The extra twist that's introduced when running stack wound with the thread coming off the top is significant within a few minutes (like taking toilet paper off the roll from the top rather than the side). Cross wound can similarly have a problem when the spool rotates with it. It -expects- that extra twist action and absent that, perhaps can cause a similar symptom. I see that twist from cross-wound rayon thread with the embroidery machine. When the twists get numerous enough, all h*ll breaks loose.

If the problem was reproducible enough, it would be worth having someone sitting with the person sewing to watch the rest of the machine but that doesn't sound like an option here. :(

Tammi,
Didn't make anything with the oiled thread, just laughed and tried it as an experiment.



Joe

How were the tension disks afterward? A little slick, I'm guessing. ;)

I know this problem is intermittent, but has anyone tried the new threading on their machine? If you have a slant that experiences this often, have you noticed any difference?

Tate

I've never experienced it and I use the original threading on all of the Slants I've used but I'm about to have another 411G show up and it's not been maintained at all in recent years. I'll compare the two that will be here and run the bejeebers (<- weird! Firefox doesn't think that's a word... :D) out of the "new" one and see if I can make it misbehave then try the alternate threading and then your alternate alternate.

How intermittent are we talking? Every couple of days... I'm going to make a lifetime of quilts before I see it... ;) Maybe in terms of hours of use is better - for me a couple of days of sewing is probably a couple of hours,...