Juki LU-563 Tension/Bobbin issue

[jerm111]

Hi Everyone,

I’m looking for some help with my newly acquired Juki LU-563. Picture of machine as it was when I purchased it (I have since rethreaded it).

I have it set up with the correct 135x17, Size 120/19 needle. Sewing Tex 70 thread.

I am having trouble with the tension, the upper thread (black) is badly showing through on the bottom side, sometimes even exhibiting slightly loose loops.

I have tried increasing the top thread tension, but it hasn’t really helped. While thinking about the lower thread tension I was examining the bobbin case area I wondered if the thread was sitting in the correct location. It is hard to see but I think it is running above the top edge of the tension spring as shown.

My initial thought was that it should be running under the spring and exiting in between the two prongs. I’m not sure of the correct loading procedure and can’t seem to find it on YouTube for this machine. It seems that when loading the bobbin, it would be difficult to get the thread into this position by hand.

I posted this on another group and was told that the tension spring doesn't look quite right and the bottom prong should also be bent inwards, into the hole. I am planning on refitting the spring or perhaps replacing it, yet to give this a try but I am hoping it will fix my issue??

What is the proper procedure to adjust the bobbin case opening lever? I think I may have messed up the adjustment whilst trying to remove the bobbin case.

Is there a way to easily remove the bobbin case without removing the gib which has three tiny screws in it? Or is it possible to adjust the tension in-situ? I'm thinking there must be otherwise this is very cumbersome for tension setting.

Any help would be much appreciated, thanks!

Jeremy

[shoepatcher]

Order a new tension spring and adjustment screw.  That one is bent.  Once you get the new one, you can see how the old one was rebent.   Cheaper than a new  bobbin case.

glenn

Edited November 14, 2023 by shoepatcher
grammar

[Wizcrafts]

Once you get your new bobbin spring, make sure you insert the bobbin so it feeds against the direction of the slot. Pull it tight and it should come out beteen the fingers on the end of that spring. That will allow you to properly set the bobbin thread tension. Do not attempt sewing with zero bobbin tension!

[jerm111]

3 hours ago, shoepatcher said:

Order a new tension spring and adjustment screw.  That one is bent.  Once you get the new one, you can see how the old one was rebent.   Cheaper than a new  bobbin case.

glenn

I have just placed an order, looks like it will take 1-2 weeks to get here.

[jerm111]

1 hour ago, Wizcrafts said:

Once you get your new bobbin spring, make sure you insert the bobbin so it feeds against the direction of the slot. Pull it tight and it should come out beteen the fingers on the end of that spring. That will allow you to properly set the bobbin thread tension. Do not attempt sewing with zero bobbin tension!

I managed to get the spring repositioned and with a few other tweaks it seems to be sewing nicely. I can get good response from the top tension adjuster.

The thread is still resting at the top of the spring though. I am wondering if I should try bending the top prong outwards slightly as it currently it is bent inwards and looks like it is stopping the thread from dropping down into the correct position.

One thing I am confused about is that when the bobbin case is located in the machine, it seems it would be difficult to pull the thread down in-between the prongs. I don't see how you would get the right angle. Perhaps I am overthinking it and all will be revealed when I get the new spring fitted?

Thanks for your responses @shoepatcher and @Wizcrafts.

J

 

Edited November 15, 2023 by jerm111

[Quade]

My singer is like this.  Top feed and vertical hook. I agree I could never tell if the thread was positioned properly.  The case opener was normally in the way. 

I had more thread jamming problems with that machine than any other.  I'm pretty sure I wasn't getting the thread into the right slot when it would jam. 

The Juki I use now, the bobbin holder comes out and you feed both in at once.  It never seems to jam up. 

[jerm111]

I've been tinkering with this machine for the last couple of months, fitted a new bobbin tension spring and using the two excellent videos (below) by Uwe Grosse I have been through all the adjustments, re-timed the machine and it seems to be sewing very nicely. 

 

One thing that still baffles me is that the bobbin thread is not in the "correct" location. The thread exits the top side of the spring as opposed to in-between the two prongs at the end and it seems to limit the precision at which you can adjust tension. I've had feedback from others that their machine behaves in the same way, so perhaps this is actually how it's meant to be? Is there any way to get a definitive answer to this?

I'm beginning to think that I prefer the design of the Pfaff 545 I used to own which has a bobbin case that is easily removed without a screwdriver. Much easier to adjust bobbin tension.

Whilst following Uwe's video and adjusting Fwd/Rev stitch balance I noticed a couple of other interesting issues.

I got the point (10:30) in the video where you loosen the screw and adjust the block to balance the stitches, the problem is that on my machine that connection is pinned to the shaft and cannot be moved.

I managed to get the stitches balanced using the under body limiter to limit Fwd and the reverse lever limiter to limit Rev.

 

The only problem with this approach is that the reverse lever was travelling so far upwards it was hitting the machine casting. The lever is attached to the shaft with two grub screws, one of which locates in a keyway on the shaft. The only way to rectify this was to adjust the lever, which means the grub screw no longer locates in the keyway.

I don't see any way to fix this issue, am I missing something here? It sews well but it bothers me that the lever is not located correctly on the shaft.

When I set the hook timing I did have to adjust the gear mesh of the hook assembly one "tooth" over, could this have put the reverse lever shaft out of phase somehow?

Any help would be appreciated, thanks!

Jeremy

[Quade]

Quote

I'm beginning to think that I prefer the design of the Pfaff 545 I used to own which has a bobbin case that is easily removed without a screwdriver. Much easier to adjust bobbin tension.

I prefer this too. The newer Juki's like my DDL-5550 and 1541, the bobbin case comes out with the bobbin when you change the bobbin, so you can easily adjust the bobbin tension away from the machine.   They both have a vertical hook drive instead of the horizontal drive like this machine (maybe I have that backwards, the bobbin case is on the end of the lower shaft).  It's easier to keep multiple bobbin cases around set for different threads too.   Stuff like this is partially why I sidelined my Singer 211 which is very similar to your LU-563.  I just don't really use it anymore but I'm loath to sell it. 

Edited February 2 by Quade

[shoepatcher]

Still the Juki LU562,563 are good machines.  They are improved copies of the Singer 111w155.

glenn