441 Clone - CLANG sound mystery.

[ShortyLV]

Thanks, everyone.

I will be going through some adjustments then.

[ShortyLV]

Thread tensions seems to be the main culprit. I have done as much to decrease tension for both sides but I am stuck - no more room to unscrew the top part (very little room to be honest).

[RockyAussie]

7 hours ago, ShortyLV said:

Thread tensions seems to be the main culprit. I have done as much to decrease tension for both sides but I am stuck - no more room to unscrew the top part (very little room to be honest).

Could you load some pics of the thread path showing the top tension discs and down on the bottom around the thread return spring? The thread return spring may be getting too much travel but the spring pressure of it may be applying too much pressure as well. It can be adjusted to give more or less if needed. The thick thread you are using may be going through too many unnecessary paths as well. Pictures will help. Did you back out the bobbin race cover screws as Wiz suggested? Some newer machines can be a little too tight in this area and may need some sanding back to allow the race to move freely as it should in there. Ideally when the screws are out about 1 turn you can easily move the race in and out and the springs will keep things in place. In your videos the screws appear to be wound in tight.

Edited January 31, 2023 by RockyAussie

[ShortyLV]

20 hours ago, RockyAussie said:

Could you load some pics of the thread path showing the top tension discs and down on the bottom around the thread return spring? The thread return spring may be getting too much travel but the spring pressure of it may be applying too much pressure as well. It can be adjusted to give more or less if needed. The thick thread you are using may be going through too many unnecessary paths as well. Pictures will help. Did you back out the bobbin race cover screws as Wiz suggested? Some newer machines can be a little too tight in this area and may need some sanding back to allow the race to move freely as it should in there. Ideally when the screws are out about 1 turn you can easily move the race in and out and the springs will keep things in place. In your videos the screws appear to be wound in tight.

I will do some more work on the machine after around a day. I'll keep you posted.

Regarding unscrewing - no, didn't get to that yet.

[milkman]

Hello,

Got myself a Sieck 441, but the one with the smaller arm. I have the same sound like you are having. I identified as being the thread snapping and moving up a bit the shuttle when it goes around it, on the bump where I am showing it witth the screwdriver. I checked Uwe's video with the timing but there he is making it for the longer arm. Not sure if this applies to the shorter, cb3200 type.

Also what I noticed comparing to Uwe's video(longer arm 441 copy) is that the shuttle of my machine has more play. Construction of the race looks different as well.

Edited February 18, 2023 by milkman

[Wizcrafts]

12 hours ago, milkman said:

Got myself a Sieck 441, but the one with the smaller arm. I have the same sound like you are having. I identified as being the thread snapping and moving up a bit the shuttle when it goes around it, on the bump where I am showing it witth the screwdriver. I checked Uwe's video with the timing but there he is making it for the longer arm. Not sure if this applies to the shorter, cb3200 type.

I've learned both from being told and experimenting that if the timing of the hook is retarded, the top thread will tend to be extra tight on the way around the shuttle and will snap. The only three solutions I've found are to either advance the hook, or loosen the thread tensions, or to increase the slack in the top thread via the check spring throw. The check spring adjustment is the easiest to make. If it works you're done. Next is backing off the top and bottom spring tensions. Sometimes that helps. The most difficult is advancing the hook and tightening down the screws without letting it move again. But, this is usually the best solution.

The only problem I've found with an advanced hook is that I tend to get more skipped stitches in reverse. It really is a balancing act. Sometimes you need to combine timing and check spring travel to nail it 100%. Aren't heavy leather sewing machines fun? Are we having fun yet?

[Tequila]

@Wizcrafts  I wish there was a “Like” button for your posts.  BTW I’m having fun but it’s only temporary 

[milkman]

On 2/18/2023 at 7:30 PM, Wizcrafts said:

I've learned both from being told and experimenting that if the timing of the hook is retarded, the top thread will tend to be extra tight on the way around the shuttle and will snap. The only three solutions I've found are to either advance the hook, or loosen the thread tensions, or to increase the slack in the top thread via the check spring throw. The check spring adjustment is the easiest to make. If it works you're done. Next is backing off the top and bottom spring tensions. Sometimes that helps. The most difficult is advancing the hook and tightening down the screws without letting it move again. But, this is usually the best solution.

The only problem I've found with an advanced hook is that I tend to get more skipped stitches in reverse. It really is a balancing act. Sometimes you need to combine timing and check spring travel to nail it 100%. Aren't heavy leather sewing machines fun? Are we having fun yet?

Super fun actually!

Advancing the hook makes total sense. Thanks!

For the CB3200 does the same timing rule apply as in CB4500? I mean the nominal hook position should be barely visible as looking from under the needle plate?

It is a cool machine. Played with it for a few days and now I'm ready to take on some projects.

I'll still have to order the slim dog and needle plate because I can see the need for it when stitching close to the edge. And still waiting for my threads to arrive.

But in the meantime I had some size 9 thread, I think thats 348 tex. Loaded top and bottom and looks nice. 230 LR Schmetz needle. About 7 mm of leather.