Bobbin wrap - What is the most likely contributor?

[Joys Shop]

There is no bur on my bobbin hook

I sometiimes would use a friend's sewing machine (I can't remember what kind it was)
it was years ago

Whenever I used it, it would jam
but he would sit down at the machine to see what the problem was, and it would work perfectly
I would return to it, and it would jam

Never jammed for him, never worked for me
I pushed on the peddle the same as he did!!!!

[baileyuph]

Slow sewing like you commented will bring out the worst in a machine. 

Next, another check is the tension areas.  Upper, lower, and the needle take up tension.

Do you have the specs on the take up spring?  That setting is a two part setting.  One is tension and the other part is duration or tension which is largely related to needle position.  Take up settings are important.

It is suggested that going through that check.  There are more checks yet, don't get discouraged. 

As a general comment, pull the feed dog plate and clean or verify that where the needle goes down is clean, fairly clean.  Remove the upper tensions disc and clean also and while your at it, check condition of disc for burs and thread grove(s).

Did the guy you compared your sewing to sew faster than you did?

Just work your way through all the checks, it is worth the trip.

Doyle

[gene]

I have a Juki LU 562, which has a smaller bobbin than the Juki LU 563. It never jams. I have occasionally spent time going through the manual and learned how to adjust the tension. I also will adjust the tension when I'm sewing thin fabrics.

My Zoji straight stitch (non walking foot machine) only needs the tension changed when I'm making zipper panels for boxed cushions. I turn the tension wheel 1 and 1/2 times and it's fined. I then turn it back 1 and 1/2 turns when I'm done.

Thanks for the info. We can save a lot of money by learning how to care for our machines ourselves. My sewing guy charges $75 per hour and if he comes to my studio the clock starts when he steps out the door of his building to get in his car.

gene

[bobbin]

Anti-spin washers?

They're standard features on full function machines because the automatic backtack function can snarl thread lickety-split.  They are available in several styles, too. 

[sofadoc]

Anti-spin washers?

That reminds me of something else to consider. The Juki Lu-1508 (top load) and the Juki DNU-1541 (bottom load) both use "M" style bobbins. BUT, if you order metal bobbins for those 2 models and compare them side-by-side, the 1541 bobbins are slightly smaller than the 1508 bobbins.

A lady gave me a box of metal bobbins that she used on her 1541. I had that problem with them unwinding and getting tangled. I threw them away and immediately stopped having trouble. I'm sure that anti-spin washers would've also solved the problem.

Pre-wound paper shell bobbins can also vary in size, depending on the manufacturer.

[bobbin]

The 1508 will accommodate a larger capacity bobbin ("U", I think) than will the 1541. 

I "roll my own" and use the metal bobbins.  And I know that the metal bobbins spin more do their prewound counterparts.  My machine (1541N7) is a full function machine (automatic tack/trim) and because of that it came with an anti-spin washer.  The automatic tack function is preset and because it's preset (and there is no adjustment of the speed with which the function occurs) there has to be a control over the revolutions the bobbin makes within the bobbin case. 

Every single full function machine I've ever met has come set up with an anti-spin washer in the bobbin case.  Every single one. 

Anti-spin washers come in a variety of shapes... a "star" or a "u" shaped affair, and probably others, too.  I've had issues with snarling on my 1541 and have investigated heavier duty anti-spin washers, but generally understand that fine tuning the anti-spin has more to do with tension adjustment than the relative "beef" of the anti-spin washer. 

[baileyuph]

Bobbin spin or backlash, what machines are more prone to do this?  Bobbin thread wrap (around outside of hook), has been stated to be an inherient issue with top loading upholstery machines.  Since the intensive analysis and calibrations on a top loader I have, the problem has not occured.  Very pleased with the outcome.  I learned that correct hook timing and  controlling thread tensions (there are more than two) are very important.

Back to bobbin spin, when a bobbin is placed in the case of an industrial sewer, it snaps in, wouldn't this lead to controlling "spin" or "backlash"?  Also to point out that the case tension on the thread should keep  the lockstitch under control.    Similar to a casting rod, provides a brake.

Sometimes our machines seem simple, then I understand everything is if you have all the answers.  Smile.

Doyle

[Toledo Mach. Sales]

Well I'll put my $0.02 in here.When the thread gets wrapped ubderneath it is usually a tension related issue or you are not holding the needle thread to first 3 stitches.If the tension(needle thread) is too loose,or not threaded correctly and you should take the upper discs apart maybe once a week (since some of this marine type of thread leaves alot of fuzz between the discs & can hold them open) & clean them.
HTH
Bob

[baileyuph]

Cleaning the tension disc, like Bob says is a likely contributor to sewing problems.


I have several machines and did exactly that and found that the thread lint/dirt (?), I call it dirt, lol, had caked up on the disc.  Cleaned it out and the tension setting could be handled much more predictable.  The stuff was caked in between the disc.

Speaking of disc, the threads many of us use today can cut a groove in the disc, another one of those aggravating tension problems.

Doyle

[baileyuph]

A comment:  my top loader that I self schooled on trouble shooting the bobbin case wrap problem was used for a project yesterday and it was very pleasing to see that machine perform like I remember it could few years ago.

All I have to do is slip the materials under the needle and sew, no knotting or wrapping.

This machine was worked on by two different techs but they charge for up to an hour of work and just moved on.  That was about $75 or so.  The machine didn't seem to need parts each time.  They improved it a bit but.....I knew it wasn't right, like it was when I bought it new. 

When I read of the bashing the top loader was taking, my intuition was how can it be true they are inheriently bad about wrapping?  Finally, I got an older tech manual decided it was time to understand it, not just read it.  It took some time.  The manual listed over 50 things to check, then I got to one that drew that........hmmmm from me.  I got into calibrating the timing of the upper arm shaft with the lower base shaft because it was just a bit off.  In essence, the tension of both threads can be perfect, the take up tension, but if these two main shafts, upper and lower aren't timed and belted that way, it causes the tension effects to be slightly off ..............while they may be set correctly (right tension). 

No more bashing of top loaders - spend the time on getting the machine right from stem to stern.

As all this started out, the project yesterday went off like a swiss watch!

Doyle

[bobbin]

I have had intermittent issues with bobbin "over spin" with my 1541, esp. with lighter weight threads.  It happens most often with 46 and 69 weight.  And it's always tension related.  The hardest thing for me has been the "fine tuning" when moving from heavy weight thread (138) to lighter weights. 

I always disliked having to hold threads for "take off" and that's one of the reasons I generally prefer horizontal axis bobbins; they tend to be gentler on "take off". 

But I still struggle with "gag ups" after take off on my 1541.  Sometimes it's great, other times it's a drag... and I'm still refining the "touch" on the tension that eliminates it.  It takes time and thought, nothing more, nothing less!

[brmax]

Bobbin I have a question on your 1541 or I guess any machine might be the same, I was curious if you always used the metal bobbins or the paper type.
Im asking because I had the opportunity to use the basic 1541 for a couple weeks and thought it was pretty darn nice machine, anyway I was informed when using the paper type bobbin the spring for the basket is not required as I didn't realize that. Just wondering from you and others your opinions with this mention.
Good day

[bobbin]

I always use the metal bobbins, brmax.  I do so much home dec. work that requires specific thread colors and different size thread that it makes sense to "roll my own" bobbins.  (I love my 1541!)