Thread Loops on top of fabric when sewing in reverse and at low speeds

increase top tension

is thread properly threaded through the tensioner and everywhere

new needle

Your needle is likely too small. Needles should be sized for thread in use, not the fabric. Guttermann sew-all is tex 30 thread, which generally calls for an 11 or 12 needle (75 or 80, for the metric needle thinkers). Not sure how available size 11 needles are for household machines, though. a dull needle can also cause this problem, because the loop formation is hindered. Nylon fabrics, and especially coated nylon fabrics, dull needles fast. So, if you have another 10 needle try it.

Make sure the needle isn't in backwards/180* and seated all the way up into the machine. I had this same problem once and it drove me crazy, until I went back to basics.

Check that the thread is following the manufactue's diagram along the complete route and then make sure the needle is in corrrect.

Jack

Patrick poses a VERY nicely worded question.
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you can ramp up the bobbin tension quite a bit, and although it will work " ok ", what thee shall reap is pulled fabric and goobers at the ends when you backstitch.
bobbins normally work well at just sliding a little bit when you bouncy/tug/drop them.

make sure that when rigging the upper thread, that where it exits from the tension disks … that it in fact does that little backwards routing affair thru the loop spring. it HAS to do that.
there is no need to thread it thru the spring, just a good tug will pop it over the lump and into the spring.
the springs can get buggered up. they are a standard part, very common, and normally the one at the sewing store will fit such as your machine.
there are found in most stores two sizes of gutterman. the big one is Not what you want for machine sewing. it does not feed at all well.
if you tear down the upper tension assy to clean it, you may find that it takes a bit of effort to get it nice nice back the way it's supposed to be.

So the thread was definitely routed correctly and the needle was inserted correctly – I checked both. I tried tightening the top thread only, but this created railroad tracks (i.e. unbalanced stitch). I also tried a bit bigger needle size (size 12 microtex) and this did not solve the problem either.

I am now thinking, as Peter suggested, that the issue is with the tensioner and the check spring. Mine is actually adjustable within the tensioner, so I think I will have a look at seeing if adjusting it to make it a bit tighter might do the trick.

I'll post back soon with results.

so ; then i got to thinking (after spending the last three hours inside one of my sergers ..), that perhaps it might pay to try sewing just a slip of paper. something appropriate, like a 3 x 5 card.
because sil is so annoying, and everything has to be optimal to get away with it. maybe try something easy peasy .. like stiff paper.

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the pos worked in the first place ? right ??
we're not chasing something left for you so step on (like a land mine), are we ?
is not a situation where you got this from your brother in law, and he foisted it off on you, after changing to a non-standard bobbin case, or such ?

so, it has been previously working correctly ? yes ?
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you can (might) find a screw hidden behind the left hand cover (that houses the up/down needle shaft) that holds the upper tension shaft into the machine.
along those lines .. when you lift the presser foot extra high, there is a rod that gets pushed which is supposed to fully open the upper tension disks.
if for some obtuse reason, this rod is always engaged, the disks won't close no how where you put the adjuster knob. and you will get zilch for upper tension. you should be able to feel the tension change when you pull the thread thru that thing and turn the adj knob.

good luck ….

So in fiddling with just about every adjustment on my machine, I happened to notice that there was a bit of varnish or sludge on the needle bar. I must have missed it due to the position I had needle bar in when I first cleaned/oiled the machine after I bought it.

Anyway, after I cleaned that off and re-oiled, the loops have gone away. My guess is that it was sticking and causing the timing to be slightly off. I think disassembling and cleaning the tension assembly may have helped as well.

The only issue now is that when sewing in reverse, the tension seems to be slightly looser (both top and bottom) than in the forward direction.

I have been posting about this in a Vintage Kenmore Yahoo Group and some others with the same machine are checking to see if theirs do the same thing. It is starting to look like this is maybe just how the machine sews. This is not too much of a problem though because I generally only sew in reverse to lock the beginning and end of seams.

Thanks for all the suggestions everyone. I will post the results of any data I get from others with this same machine.

-Patrick

> there was a bit of varnish or sludge on the needle bar.
Yeah, been there once before.
Bought a cheap Asian (Taiwan or Japan?) sewing machine in the very early 70s. It wouldn't sew much at all. Turned out the mech inside was covered in protective shipping grease which the importer had not cleaned up. So I stripped it down and cleaned it w kero, then oiled it.
After that the thing sewed excellently. The main shaft just floated in the cast iron bearings like a dream. Tolerances were beautiful. Really well made.

I wonder how many people bought one and threw it out when they could not get it to sew?

Cheers

So it’s been a long while since I’ve posted on this.  Never did get any response back from the other forum.  I’ve since bought a straight stitch only machine – a vintage Singer 15.91 – for straight stitching and sewing thick stuff.  It does a beautiful job of both.  The Kenmore is a fine machine, but what can I say?  I like vintage sewing machines. The looseness when sewing in reverse with the Kenmore seems to be due to the fact that on that machine, the feed dogs always travel the same distance when sewing in reverse regardless of the stitch length you’ve set.  So when you’ve got a bit longer stitch length set, it feeds a bit more thread than is needed for the length of the reverse stitch.  Not really a problem if you just need to lock the stitch at the end.  I’ve also taken to turning the fabric around to lock stiches since with really lightweight fabrics like Membrane 10 from RBTR,  sewing in reverse just causes the fabric to get sucked into the feed dogs.

sometimes you can pull light fabrics sideways to keep it from bunching up on feed dogs

annoying that it does that