Cobra 26 needle missing needle plate hole

[falling4u]

We have watched the videos online, but haven’t found any forums or videos on this…. When the needle hole plate is not lined with the timing of the needle. Needle does not go into hole hits top of plate instead. What should we do for timing or adjustments? Our timing with bobbin is correct.

[Burkhardt]

The needle shouldn't go through the needle plate

[Wizcrafts]

2 hours ago, falling4u said:

We have watched the videos online, but haven’t found any forums or videos on this…. When the needle hole plate is not lined with the timing of the needle. Needle does not go into hole hits top of plate instead. What should we do for timing or adjustments? Our timing with bobbin is correct.

The Cobra 26 is a compound feed walking foot machine. There is no needle hole in the throat plate. The needle hole is inside the feed dog. The throat plate has a rectangular cutout to allow the feed dog to move from front to back.The needle bar moves in sync with the feed dog and inside foot. The needle should always go through the hole/slot in the feed dog.

[kgg]

8 hours ago, falling4u said:

Needle does not go into hole hits top of plate instead. What should we do for timing or adjustments?

As @Wizcrafts said the needle plate has a square slotted cutout to allow the movement of the feed dog from front to back. The Cobra Class 26 is basically a clone of the Juki LS-341 / LS-1341 and has a hole in the in the feed dog with the standard inner presser foot also having a hole. The needle should always go through the center of the hole in the inner presser foot and move front to back in unison. Also the needle will go through the center of the hole in the feed dog and also move in unison with the the needle.

A couple of things to check:

i) Longitudinal position of the feed dog (page 2 of manual)

ii) Lateral position of the feed dog (page 3 of manual)

iii) Needle-to-hook timing (page 6 of manual)

iv) Feed cam timing and Feed motion (page 12 to 16)

I have attached the Service Manual for the Juki I am referencing.

 

kgg

Juki LS-1340&42 Servcie Manual.pdf

Edited May 29, 2023 by kgg

[falling4u]

I may have called the parts incorrectly. Attached a photo! The machine worked like a dream, and we've had problems since we changed the stitch length. 

[falling4u]

8 hours ago, Wizcrafts said:

The Cobra 26 is a compound feed walking foot machine. There is no needle hole in the throat plate. The needle hole is inside the feed dog. The throat plate has a rectangular cutout to allow the feed dog to move from front to back.The needle bar moves in sync with the feed dog and inside foot. The needle should always go through the hole/slot in the feed dog.

 

[AlZilla]

11 hours ago, falling4u said:

Our timing with bobbin is correct.

It looks like the manual kgg posted above is the cure.

I'm curious how you know the timing is correct. If the needle doesn't descend, you can't compare the nook to needle eye position. Maybe you have a misunderstanding of how the timing works?

[falling4u]

41 minutes ago, AlZilla said:

It looks like the manual kgg posted above is the cure.

I'm curious how you know the timing is correct. If the needle doesn't descend, you can't compare the nook to needle eye position. Maybe you have a misunderstanding of how the timing works?

The timing with bobbin is correct, we have removed the screw for the plate so we can see the needle eye position with bobbin. But when we reassemble, the needle is still ahead of the hole. Prior to this happening we were completing many peojects. According to the Leather sewing Machine Co  instructional videos, things should be correct. ....somewhere along the line of sewing, this plate got in the way and cannot get the needle to decend back into the hole. Thanks everyone for the manuals and replies

[kgg]

1 hour ago, falling4u said:

somewhere along the line of sewing, this plate got in the way and cannot get the needle to decend back into the hole.

The needle is striking the feed dog so the position of the feed dog needs to be adjusted so readjust both the Longitudinal and Lateral position. This may have occurred if the height of the feed dog was set to high above the needle plate and the inner presser foot slammed it out of position.

kgg.

[AlZilla]

1 hour ago, falling4u said:

The timing with bobbin is correct, we have removed the screw for the plate so we can see the needle eye position with bobbin. But when we reassemble, the needle is still ahead of the hole. Prior to this happening we were completing many peojects. According to the Leather sewing Machine Co  instructional videos, things should be correct. ....somewhere along the line of sewing, this plate got in the way and cannot get the needle to decend back into the hole. Thanks everyone for the manuals and replies

I understand, thank you. When you're saying "the plate", I think what you're talking about is the feed dog. So you apparently removed the feed dog to check the hook timing - smart, I think, since it lets you isolate the problem.

I learn a lot following these things and it sounds like you're well on the path to getting it fixed.

[dikman]

From the look of that feed dog it's been hit a few times with the needle.

[Wizcrafts]

The feed dog is way out of position.