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Sewing Gurus, what do you think is going on here?
http://i629.photobucket.com/albums/u...1043Medium.jpg
Sewing baffles into my UQ. Mara 70 bobbin and thread, Brother 6000i, 12 or 14 needle isn't new. Every time I get going a little fast, over half speed or so, I get a jam up. I'm getting near the end of the thread and it starts dancing around some when I get going fast, causing some slack I think...
Wonder what the culprit is likely to be?
It looks like you are not getting the bobbin wound smoothly at the start. Winding the bobbin needs to medium speed and very smooth from the very beginning. It is important to maintain a steady speed and not bounce fast to slow to fast jerk and stop.
The same thing can happen with a spinning reel... birds nests. Real pain.
That's my assessment from the photo.
Thanks RamblinRev. I was hoping you would be on call. :)
Well it happened on two different bobbins and I'm real careful about winding them evenly. Decided to change to a fresh #10, swap out bobbin and go to a new spool of Mara 70.
Can't argue with that logic! Working fine now!
I spoke too soon...
http://i629.photobucket.com/albums/u...1050Medium.jpg
:crying
Thing is, it flies through my test fabric, t-shirt cotton. Guess I'll just try to limp through this project more slowly. Rats.
All this thread ends up jammed in the throat.
http://i629.photobucket.com/albums/u...1052Medium.jpg
Did you state your needle is NOT new? Put in a NEW needle. Your thread looks heavy is it? Your thread and needle need to match, a couple of prior posts have the types of threads that go with different sizes of needles and fabric.
Get in and clean your machinge, take the bobbin apart clean everything, look for the nasty little threads of parts of thread or lint hiding, use a little compressed air to clean everything.
I bet you have a little lint or bit of thread boogling up the action of the bobbin. Maybe check to see if your timing is correct. Are your feed dogs engaged correctly?
If all else fails have someone trustworthy look at your machine.
Try putting a little less thread on there. For starred take of @ 1/16 and spin it up. Had same issue on my zig zag. I never fill them up all the way to when the machine says its full.
Also double check your needle isn't 180* out. I had mine in backwards and worked great on everything until my main fabric. Even worked at slow speeds. Soon as I hit the go pedal I was hosed
It wasn't a new needle but it is now. I swapped it before that last fail. Can't put the needle in this machine in the wrong orientation. I've sewn a thousand miles with this needle thread combination.
I'll clean it out and load a fresh bobbin and see if that helps.
Thanks everybody!
Maybe a heavier duty needle?
If that thread is heavy, then it will retain a lot of spring from the stiffness. But it is only Tex40, medium strength for buttonholing. Maybe it is bonded, the treatment reducing its limpness.
But, I've gone through bobbins full of Tex69 and Tex92 threads in a Class 15 home machine, without the problem you show, which looks like a spinning reel after a cast not concluded with a thumb on the reel. I've been lucky, or maybe sewing more slowly, or maybe winding the bobbins more slowly and smoothly than your sm does.
Right DemostiX. It's only Tex 40 and not stiff at all.
Ever fix something by taking it apart, looking at it, and putting it back together?
I think I have it solved by cleaning. Had cleaned it not that long ago and didn't think it needed it but it's running much better now and I can go faster. Even sounds better.
I hope that's solved it...
HFG
I agree with giving it a good cleaning and inspect carefully for burrs on the rotating hook, etc.
Triple check that the bobbin is put in with the thread coming off of it in the correct direction.
FWIW, I routinely sew 1.0-1.9 ripstop with Mara 70 and a #11 needle so I doubt you need a larger needle.
Right. I usually use a #12 on ripstop, but this #10 is new and working fine.
I must have blown something out that was jamming it up.
So far so good!
The wife and I still come back to a winding problem. Make sure you are threading the machine properly to wind the bobbin. There is a tension mechanism the thread goes through. Sometimes it is the usual tension discs but I think more often it is a separate thingie. That keeps the bobbin winding properly at the right tension to make the layers smooth. Also make sure your bobbins are not damaged. Any spurs or rough spots on the sidewalls and create problems with the winding pattern. Bobbins need to be replaced after a lot of use. Admittedly it is not an every day or every month kind of thing, but it couldn't hurt to inspect them every 6 months or so and replace them every year or two. Especially the plastic ones.
Thanks for putting your thinking caps on! So do you think I'm winding too tight or just unevenly?Quote:
Originally Posted by Ramblinrev
I will definitely check that out and as I've gone through several bobbins on this project, I need to wind some anyway. I'll definitely inspect them as well.
Thanks again RR
More likely not tightly enough. That would allow the layers to shift in the bobbin and bind each other.Quote:
Originally Posted by hppyfngy
Be careful about overfilling them. Usually at least 1/16" needs to be left empty on the bobbin spool. In theory the winder should self cancel when the bobbin is full... but you know theories.
RR, you certainly have vastly more experience than I do but I'm confused about this theory based on what I'm observing.
When this happens, it acts as if the feed is slipping. In other words, as if the fabric were not being fed properly. The fabric seems to suddenly slow it's pace being fed and in half a dozen stitches, grinds to a halt.
However, if I switch to a thicker cotton material, I can zip through it at much greater speed with no problems. Same thread, needle and bobbin.
Now I freely admit that I don't fully understand what goes on under the throat plate. As far as I can decipher there may as well be Gremlins or even Black Magic at work under there. I mean I know what happens, but it's almost unfathomable to me how it happens so fast.
So I will defer to your superior knowledge and accept that it's either user error, a not so great machine or whatever, but I don't really understand why it works flawlessly on one material and not on this thinner slipperier one, unless it's simply slipping and then binding up.
I'll redo my bobbins though and let you all know the results. Tomorrow. I think I'm done for the day.
Time to splice some amsteel. I can wrap my head around that! :laugh:
Thanks again!
HFG
You know that the tagline someone here uses, 'The tension makes it work", must have originated with a sewist cracking wise.
As long as the tensions are balanced between the one on the bobbin thread and the one up top, you can sew and all is cool. ( I'm not saying the stitch will be optimal if they are both loose or both tight, but allow me, so I can get to the point:)
You know that the tension on top is supposed to be set by the discs the thread passes through, and that posts and threading prior to that are there just to set a smooth stage, not to add tension to what will be supplied and released by the discs. Well, there's a similar thing going on in the bobbin case. If , as per my previous paragraph, the tension is set high, variations in the tension of the thread coming off the bobbin will be somewhat swamped by the tensions in the bobbin case and high offsetting tension up top. But, if the tension in the bobbin case is just right-- as it is supposed to be -- then variations in bobbin winding and snags of thread coming off buried layers on the bobbin will cause the stitches to be irregular in quality. And you could also get just what you were seeing: the thread stretches a bit -- and poly will, per spec, by 10-20% --, energy gets stored in the bobbin, and then the snag releases, causing the bobbin to spin forward, un-spooling thread and giving you that spool mess.
Well, that's one explanation for it. Which might even be correct, as I'm learning a lot by doing a lot that's wrong......including setting high bobbin tensions to give me some range in setting tension up top.
One other thing: Some would use one size larger needle than you are for tex40-size thread. And there ARE variations between brands and between needle types in the size of the hole for a given size needle. That is not to say you should use some size or type, but that when you change to another that you think is the same, you may get different results because the eye is different.
In theory, the lighter fabric should require less tension on the thread, although I don't see this causing your problem. It won't hurt to experiment.Quote:
Originally Posted by hppyfngy
I'm guessing the slowing of the fabric feed indicates things are going wrong with the bobbin thread rather than the slowing down causing the fowl up below.
How a stitch is formed...may help you understand how this happens.
Edit...Demo's post makes some good points. The stitch is formed so fast that it takes very little to throw it off sometimes. I would try going back to size 12 needle if that worked in the past.
Sewing 101. I probably need that class.
Thanks gents.
A problem with the sewing tensions should not affect the bobbin in that way. Assuming I am looking at the photos properly the snarls are all coming out of bobbin. Now it _is_ possible the type of material changes the way in which the bobbin is drawn down. But a properly wound bobbin should not do that at all.
Do you completely empty the bobbin before rewinding it? You should.
I had a similar issue with my old machine where the same bird's nest would form, but it would form between the presser foot, the feed dogs (the 'advancer' that moves the fabric) and the top of the bobbin race - almost like the feed dogs weren't causing the fabric to advance, and there was excess top tension yet an abundance of excess thread from the bobbin which would then bird's nest at the top of the race.
If I kept the material I was sewing taught then this bird's nest wouldn't happen, but the second I would let go and try to continue to sew it would happen. The feed dogs would work, but it was almost like it was out of sync.
Now, full disclosure - that machine was already a refurb, so who's to know what the previous issues with it were, but I ended up getting so pissed that I bought a new one. As in a real new one...
The race was vertically oriented, where as the new machine has a horizontally oriented one. Another thing to consider is if your machine has different 'programs'. Depending on the program that your machine is set to, it may turn the feed dogs off, which could present the same issue I had, except that my machine didn't have a setting/program to turn them off. I know it doesn't help you much as I haven't been able to provide any resolution, but I would recommend either taking it into a repair facility or ringing the manufacture (or just ring the repair shop) and trying to get on the line with their support folk.
Maybe its just something simple (... :D ...) like an adjustment, a quick tune-up, or program/stitch setting. Maybe its something stupid like a piece of excess material that's fallen inside and is knocking the thread at a certain point with all of the right conditions.
Well, I just don't know what to make of this thing. I've changed back to a new #12, taken it apart and cleaned it yet again, checked my tension, spun up two fresh bobbins with great care, and I can still only go half throttle.
It's too new for the dogs to be worn and the bobbins are new. The bobbin case is perfect.
The jam up starts with a kind of a thump, like something hits something. It's muffled and not metallic and not that noticeable, but you feel it. The birds nest is all below the plate and I have to cut the thread with a seam ripper to release the fabric.
Good news is I can stumble along at half speed and that's almost as fast as I can go anyway. (Fold and sew, repeat... 6-8 inches at a time...)
Might have to take it in and have it checked out after all...
This recent sewist does not exercise the discipline to make sure everything is done right before making changes. No point in making adjustments to tension to bar tack some heavy straps, if I have not taken care that the top thread has not become dislodged from the staging point above the tension assembly. Because if it has become dislodged on this sm, it falls OUT of the tensioner, creating, of course, a bird nest beneath the plate and above the bobbin case. Duh, but I wasn't paying attention that every stage of the set-up remained intact while fiddling with one. Don't make my mistake.
Along with RR, I misunderstood, until your recent post, where the bird nest was. On your report, that nest is typical of lost tension regulation during stitch formation. Stitches are not being pulled up tight. Your description of the feel is exactly what happens when multiple loops of thread are being pulled between bobbin case and housing in a space designed for the thickness of just one thread.
Be sure the top thread is down between the tension discs, not floating halfway. Or, if your machine isn't old enough to be served alcohol, follow your manual regarding needle bar position when you thread it into the black-box slots. If problems persist, cleaning of the tensioning mechanism -- a pair of kissing lip-disks on machines old enough to drink (and old enough to be long-dead of cirhossis)--is called for. At the least on such oldsters, you can slide a fabric strip between the discs to clean out lint.
Ok... we now have a better idea of what is going on. First of all check you spool (upper) tension. The easiest way to do that is to thread the machine and the needle. Don't worry about the bobbin right now. Put the needle and the take up lever about half way with the presser foot up. Now pull on the tag end of the needle thread.Quote:
Originally Posted by hppyfngy
Lower the presser foot (don't catch the thread) and pull again. You should feel a significant difference between the two pulls. The pull with the presser foot up should be much easier than with the presser foot down. If it is not then you have a problem with the spool tension system which will do exactly what you are describing.
Also check the needle plate for any nicks or burrs. Really any nick or burr that the thread goes by AFTER the thread take up lever.
I would suspect you either have a tension problem or your thread is getting caught somewhere and not getting pulled up by the take up lever.
With the presser foot up there is almost no tension. In fact there may be nothing but friction. With the foot down there is considerable tension.Quote:
Originally Posted by Ramblinrev
I think it passed this test.
That is the way it should be. Turn the upper tension to its maximum and try to sew. If it still happens then Pag is most propbably correct. There is a burr somewhere. Ideally your upper tension should be set around the center of the range.Quote:
Originally Posted by hppyfngy
Is the bobbin installed properly? There is a right and wrong way...
I've seen this when I'm going to fast, and the bobbin thread pulls out of the tensioner...
With Tex40 thread, I normally use a bigger needle... seems to work better on my crummy machine..
Thanks John, et al.Quote:
Originally Posted by JohnSawyer
The bobbin is installed correctly. I'll also try a #14 but I've sewn a ton with #12 with no issues before. I dunno.
I have read on other forums that using metal bobbins in this particular machine makes a world of difference. You better believe I'll be looking for some tomorrow.
Spit-balling here since nothing's been resolved yet:
- If it's happening on the lightweight fabric only, ensure the fabric is reasonably snug on each end of the presser foot by holding it
- This happened to me when using the Tex 75 + Polypro webbing. I had to up the needle size to a 90/14, and crank the tension up to get it to stop birds nesting.
- Your feed dogs are still gripping well on this fabric?
- check to make sure that your 'new' needle is still nice and straight. The last time I heard a pop like that, my needle had a little bend in it which caused this exact problem up until I replaced it.
If your needle is straight, perhaps there is some misalignment with the bobbin assembly?
Good luck!
Thanks,
Recapping and a little minor info. I said before it didn't happen with t-shirt material, but I was wrong. When changing the bobbin after the birds nest happened, I would run a line of stitches in a scrap of t-shirt and it seemed to be perfect. Going back to the 1.1, it would fail, but only after going faster than half throttle. But last night I tried faster speed with the cotton and got the same darned thing.
One other thing. I believe I can go at any speed, so long as I hold my fabric as it exits and apply a slight pull, assisting the feed by not letting it go slack. Not really pulling, just applying some tension to the exiting fabric. (I'm not 100% sure about this but I'll test it...)
But the birdsnest only happens if I am going faster than half throttle. If I set the regulator to limit it to half throttle, I can sew all afternoon at any speed up to that point.
I still want to try a couple of things but I've been elbow deep in down this afternoon stuffing an underquilt.
I know my needle is new and straight. I usually use a #12, but I'll try a #14 and I'm gonna find some metal bobbins and we'll see what happens tomorrow.
Now I have another down pillow to kill.
HFG
One more thing to try. I know you have brushed out the bobbin area to clean it... but have you actually removed the throat plate? That's the thing feed dogs come up through. There should a some screws holding that to the bed. If you have not removed that, do so and inspect every thing you see. Some where you are having a mis match between the movement of the fabric and the speed of the needle. The timing should not be a problem because that would tend to drop stitches. But maybe there is slippage in the feed dogs which kicks in at the higher speeds.
+1 on what rev said, and while it's off make sure you don't have any damage to the edges of the feed dogs. I had a small gouge on the side of a feed dog on a kansai that would make the dogs bind at higher speeds. Once those started to catch the hook would jerk (same drive shaft) and drop the stitch causing birds nests. A little dremel action and bob's your uncle.
Check your bobbin case. The grey plate should slide right off. The black case the bobbin sits in may not be installed correctly, there are usually two white lines that should line up to indicate proper alignment. If the case is twisted to far in one direction or the other the tension of the bobbin when the hook spins will be all out of whack. I see this all the time after some one cleans there machine.
Try adjusting needle position all the way to the right once...just curious
A description of almost a charmed life:Quote:
Originally Posted by hppyfngy
Gets "to sew "all afternoon"" if you "limit it to half throttle." Why, the musician and happily married Sting made famous his endorsement of methods for another activity a decade or two ago with a similar claim. "Tantric" something or other.
Not "Singer" or "singing", for Sting. Where does my memory fail?
RR (or anyone knowledgeable.) In your experience, can you always remove the feed-dogs for inspection and cleaning that area without threat to upsetting alignment or timing, at least on older serious SMs? In other words, is that single maintenance independent of the mechanisms for timing and alignment, or does it depend on the make and model of the SM?
Quote:
Originally Posted by DemostiX
Well, I've always had an "almost charmed" life. :)
And while I don't necessarily consider sewing to be a sacred act, I can and will "sew" all afternoon when given a chance.
;)
its the tension is too loose
If that's all that is going on it would react the same whether sewing fast or slow. That's certainly a part of it but not the whole problem.Quote:
Originally Posted by hang10
Well I haven't made any revelations but I did get a notion from Knotty, who has the same machine I think.
He has had some similar problems when sewing very thin material like the 1.1 I'm using now and thought the problem seemed to be as if the fabric were getting pushed into the throat.
This is consistent with what I'm observing as well. If a stitch doesn't penetrate the fabric for whatever reason; slack or slippery material, dogs not holding, dull needle, I think you would get the result I'm getting. A buildup of bobbin thread below the throat. If I provide extra tension to the fabric as it exits the dogs, you can see that I am not allowing the fabric to go slack.
I don't think it's tension of the thread. I think I've checked that and just seeing the stitches makes me believe it's fine.
I have more testing to do but at the moment I'm just thinking this Brother just doesn't grip the fabric effectively enough to move this thin slippery stuff through the dogs at a high rate of speed.
Why that is, I'm not sure.
HFG
What you've written is entirely plausible: You don't get, except maybe if you know how to tweak, all the performance from a basic lightweight machine that you might expect of one that was built of cast iron and was expected to hold tolerances running full throttle. (And even then might have problems with fabric as slippery as sil.) Those feed dogs are not only doing a lot of work, the grab, pull, and release all have to just right.
On a sewing forum, a buyer of ancient iron expressed surprise that her new (to her) machine did not include the couple or few feed-dog height settings she was used to seeing on ordinary sm's. (eg silk, normal, none (feed dogs lowered). On a really prime old Singer or Pfaff or Sears, she just got all or nothing. It occurred to me that in-between settings were no doubt nice to have, but tens of millions of sms had been built for a hundred years without that marketable feature, with sewists expected to acquire skill in matching presser-foot tension to job requirements instead. Or the orbital action of the feed dogs built-in was such that skill of that kind wasn't so much required.
So, the thrill of letting 'er rip at full speed may have to be deferred until you are working with different fabric.
Or, a different type of needle may let you sew faster, which would be important in a production environment. Maybe, for example a sharper microtech needle from Schmetz would work better at high speed than the more parabolic-pointed "universal" needle that dominates the market. http://www.schmetzneedles.com/learni...dle-primer.htm. Here (or elsewhere) there are sewists who can't abide universal needles. I presume it is at speed that the compromise in that design shows up.
Right. And there is also no way of adjusting the presser-foot pressure. It's automatic.
This is a very smart machine, and I'm not going to complain about it. I think I've just found a limitation.
I don't need to hurry, in fact I don't believe in it. But I do like things to work as they should. Maybe this is just how this sm works.
Thanks all, it's been a learning experience. I'll report back if I discover any new information.
Cheers,
HFG
See if you can find a "straight stitch" throat plate for that machine either from a dealer or after market. It has a small single hole in the plate which makes it much harder for the fabric to push down in.
Now to throw in a wrinkle... many of those older machines were able to sew china silk which is every bit as sheer and lightweight as 1.1 nylon if not more so. Check you needle to see if you are using "ballpoint" instead of universal or sharps. If possible, use only sharps for those very lightweight fabrics.
I did this once when I had a similar prob..
Stick a small piece (2"x2" approx.) of blue painters tape under the foot on the plate. Spin the machine a few times to pre-punch the hole. The tape will support the fabric (at least it did my experience) and it still allowed the stitch to travel thru. Trim the tape so the dogs are clear.
And the tape increases the foot pressure, so to speak, by decreasing the gap some.
I know you cleaned it once before, but check for some debri under the stitch plate where the dogs travel. Some fluff can make it hard for the dogs to travel properly.
I was guessing at fabric deflection and that's why I asked to set needle all the way to the right (putting the needle close to the needle hole edge on the throat plate). Sometimes having the fabric supported by 3/4 of the sides makes the difference.
Lurk'n & learn'n. Appreciate the info provided as I make a few things with my "new" 1967 Emdeco machine. My collection of needles seems to have been growing as has my thread inventory.
I was sewing with the needle all the way to the left, providing the support you describe. I feel certain after some more experiments with other fabric, other needles and several cleanings that this is a limitation of this machine. You just can't haul a$$ with it, especially with very slippery thin fabric.Quote:
Originally Posted by Pag
I'm resigned to live with that.
Same topic just came up in one of the yahoo sewing groups. Besides the tape afixed to the zig-zag plate, one of the commenting sewists said that he / she sometimes affixed slippery tape to the underside of the presser foot. It's up to you, of course to carefully cut and trim the smallest holes in the tapes for the needle.Quote:
Originally Posted by hppyfngy
Necchi used to think this could matter with silk. A straight stitch model with a rotateable circular faceplate includes two straight-stitch holes, one of them smaller than the other to minimize fabric deflection by the needle.
On needle position (left, right, or center): Left may be different from right in performance on some sms that don't have the bobbin case and hook move left and right with the needle.