Singer 29K71 – Skipping Stitches / Thread Not Catching – Shuttle Carrier Play

[DmytroH]

Hello, masters and experts,

I recently got my first industrial sewing machine – a Singer 29K71. At first, it seemed to work perfectly, stitching reliably through different leather thicknesses. However, within just a few days, it started skipping stitches or not forming stitches at all, making the process of crafting products frustrating, to say the least.

Now, sometimes it sews perfectly, but even small actions – like lifting and lowering the presser foot – cause it to suddenly stop making stitches. The thread just slips through and doesn’t catch. At this point, I'm even afraid to breathe near it, not to mention changing the bobbin.

I’ve read a few forum threads and suspect that the issue might be due to at least play in the shuttle carrier (82177). You can see the movement in this video: YouTube Video

Could this clearance be the cause of the problem? If so, could you advise me on what to disassemble and check to take more detailed photos for investigation? Or is there something else I should inspect besides the Shuttle Driver Gear Box (82226) and driving pinion (82178)? Could the issue be even deeper?

I know that many people mention the small bobbin capacity as a downside of this machine, but for my initial learning in leather sewing, it’s more than enough before transitioning to more advanced and expensive machines. That said, I’d love to restore and bring this beautiful machine back to life.

Since this is my first machine, I truly appreciate any help and guidance. @Wizcrafts and @Constabulary, I’ve seen your insights on similar machines – would love to hear your thoughts!

Thanks in advance!

Edited March 4 by DmytroH

[shoepatcher]

Gears and rack are worn.  Too much play in those areas from your video of the shuttle carrier.  With no wear, the shuttle carrier should  hardly move when you turn it by hand.  You look at the drive pinion, following pinion, short rack and long rack for wear.  Also check the bushing that the shuttle carrier shaft goes thru.  You might have to replace all of those as well as the bellcrank.   I have rebuilt shoepatchers for over 45 years so I know what areas to look at.

glenn

[DmytroH]

Hey Glenn,

Thank you for your advice, I really appreciate it!

I’m attaching photos of my parts – maybe with your experienced eye, you can tell if they look too worn or still usable when you have a chance.

I’ve got a couple more questions:

1. Bushing – I’m attaching a photo of what I think is the bushing that the shuttle carrier shaft goes through. Does this look like the right part? If so, could you please suggest the way how can I remove it properly? If this isn’t the bushing (82179) you meant, I should mention that I didn’t find anything between the shuttle carrier (82177) and the shuttle pinion (82178).

 

1. Removing the Long Rack – I haven’t taken out the long rack (82175) yet. Any tips on how to remove it safely?
2. Bellcrank Lever (82167) – I haven’t checked this part yet since I’m not sure how to get to it. If you have any advice on that, I’d really appreciate it.

Thanks again, @shoepatcher for taking the time to help me out!

Edited Thursday at 06:46 PM by DmytroH
attached new photos

[shoepatcher]

Put the shuttle carrier shaft in the bushing and see if it wiggles.  Is so bushing is worn and needs replacing.  bushing are pressed in.  My late father came up with a way to remove the bushing a with a nut, bolt and big washer.  can remove old one and replace with new one with those 3 items.  The shuttle carrier should just turn in the new bushing with out any wobble.

 

To take the long drive rack out, there is a connecting screw in an access hole in the back.  Screw #89.   That release the long wrack.   I normally have to pull the replaceable horn to replace the drive rack,  The teeth on your drive rack look go.  Chances are wear is in the drive pinion and the following pinion.  I will also tell you the bell crank is probably worn as well.  To replace that you have to take the end of the head off.  4 screws hold it on.  You also have to drive the piston pin that connects to the needlebar out.  It is a tapered pin that drives out from back to front.

glenn

Just now, shoepatcher said:

Put the shuttle carrier shaft in the bushing and see if it wiggles.  Is so bushing is worn and needs replacing.  bushing are pressed in.  My late father came up with a way to remove the bushing a with a nut, bolt and big washer.  can remove old one and replace with new one with those 3 items.  The shuttle carrier should just turn in the new bushing with out any wobble.

 

To take the long drive rack out, there is a connecting screw in an access hole in the back.  Screw #89.   That releases the long rack.   I normally have to pull the replaceable horn to replace the drive rack,  The teeth on your drive rack look good.  Chances are wear is in the drive pinion and the following pinion.  I will also tell you the bell crank is probably worn as well.  To replace that you have to take the end of the head off.  4 screws hold it on.  You also have to drive the piston pin that connects to the needle bar out.  It is a tapered pin that drives out from back to front.   short rack looks good.

glenn