Juki 1541S bobbin case problem

[gottaknow]

That black thingy is to prevent backlash. Backlash occurs when you stop sewing suddenly and the momentum of the bobbin unwinds thread inside the bobbin case. The little arms press against the bobbin acting like a brake for the bobbin. High speed garment machines must have that operational or you have a continual mess. 

As for your bent bobbin case, find a socket that fits closely to the inside diameter of the bobbin case and simply use a small ball peen hammer to straighten the case. No real need to replace it unless it's cracked. This happens everyday in the factory. I have a special insert made for doing this, but a socket works fine. 

Regards, Eric 

[RockyAussie]

Now that is something worth learning and I must say that gottaknow's input and Uwe"s into this forum alone makes it worth visiting. That tip is well worth remembering.

[stickandtin]

Great advice Eric and Uwe. Thanks for the help.

[Mike516]

10 hours ago, RockyAussie said:

Now that is something worth learning and I must say that gottaknow's input and Uwe"s into this forum alone makes it worth visiting. That tip is well worth remembering.

Yes, this is good info. Must remember this.

[suzelle]

This may sound crazy, but I have at times (when bobbin spins without a backlash spring) cut my own little disk from a piece of paper and inserted it in where the backlash spring sits. Crazy maybe, but it works. I don't have so much of a problem when using paper sided bobbins, pre-wound. It's the metal bobbins that spin like that. I really dislike those backlash springs and pull them all out of my bobbin cases.

[gottaknow]

2 hours ago, suzelle said:

This may sound crazy, but I have at times (when bobbin spins without a backlash spring) cut my own little disk from a piece of paper and inserted it in where the backlash spring sits. Crazy maybe, but it works. I don't have so much of a problem when using paper sided bobbins, pre-wound. It's the metal bobbins that spin like that. I really dislike those backlash springs and pull them all out of my bobbin cases.

Great point. Also place one drop of oil on the paper. Helps a lot. Now before everyone stuffs their bobbin cases, you have to check that the bobbin tension is the same with whatever you insert. Too thick and your bobbin tension will get too tight. Also, aluminum bobbins backlash less than steel, simply from the weight.

Regards, Eric

[gottaknow]

Here's my bobbin case repair stash for horizontal bobbin cases. The tool for straightening bent cases is shown there. I have several, but I think this one's from the 70's and was sold by Singer. There are adjustment screws in the antique Singer needle box in an attempt to contain them.

Regards, Eric

Edited June 17, 2016 by gottaknow

[stickandtin]

Tried the socket approach to getting rid of the dimple. My sockets have rounded edges so couldn't get close enough to the dimple. Went with the dremel tool and had success polishing off that dimple. Put bobbin back in basket and everything works perfectly. Wife is sewing merrily along again. Thanks everyone for the help.

[Rangeleather]

Hey Eric or anyone,

Do you know which way the little black tin thing goes in?  It seems that it is convex/concave and I'm trying to figure out which way it goes in.

Kyle

 

[mikesc]

When it is in correctly, "the little arms" should be sticking up slightly nearer to you ( and therefore the bobbin ) than to the base of the case..it is the arms that touch the bobbin, and prevent the "backlash", not the centre of the disc.
HTH