29-4 looping incorrectly

[Ole South]

Singer 29-4 (circa 1915 I think, treadle driven) suddenly began to loop beneath the shuttle carrier (p/n 8506) rather than sliding under the shuttle/bobbin assy.  This leaves long loops on the underside of material and/or jams.  Timing appears correct, hook catches loop every stitch, and I've changed hook and bobbin with multiple known good parts.  Upper threading is correct and very little rotational and/or vertical slop on the shuttle carrier itself.  Upper tension seams correct.  I've tried tapping the shuttle drive cog up to reduce any gap between the bottom of the shuttle carrier and the arm cavity, but problem persists.   Anyone have advice?

The head was rebuilt about a year ago and unit was sewing well with 6-7sti thru most material.  I don't see a set-screw to affix drive cog to shuttle carrier drive shaft like the 29k's have so am assuming this is a pressure fit... can someone verify that for me too?

Thanks 

[Wizcrafts]

Maybe the timing is retarded due to slop in the gears. Does your 29 have an adjustment hole on the front of the base, where a screwdriver goes in to turn an eccentric screw that advances or retards the timing?

[Constabulary]

AFAIK the early 29 & 29K do not have a timing eccentric. I would guess racks and pinions are worn out. But they are obsolete - however with some luck you still can find some NOS parts. But they are very rare.

This thread may be of interest for you.

 

Edited November 2, 2022 by Constabulary

[shoepatcher]

14 hours ago, Wizcrafts said:

Maybe the timing is retarded due to slop in the gears. Does your 29 have an adjustment hole on the front of the base, where a screwdriver goes in to turn an eccentric screw that advances or retards the timing?

WIZ.  29-4 did not have an eccentric for timing the shuttle.

glenn

[Ole South]

How does one remove the shuttle carrier on these Oldies but Goodies?  I am not seeing a set-screw like the 29K's have.  I've pulled the unit into the shop and am thinking there may be a loop or three of thread under the carrier from a jam lifting it enough to allow the loop to be passed UNDER the carrier rather than just the bobbin/shuttle... especially considering the hook never misses a loop.

(and no... no timing hole.  I need to check the serial but I think this is a somewhere 1911-1915ish unit)
Thanks Cons... that link was wonderfully interesting.  Is anyone pursuing a similar path for the 29- series? Doesn't appear many of the parts listed are interchangeable.

Edited November 2, 2022 by Ole South
addendum

[Ole South]

Oh my goodness, it's a hex set screw in the drive pinion to remove.  So didn't expect that.

Okay, got the shuttle carrier out. Thread wad under it. Once removed found way more slop in vertical axis.  I'm going to try and shim the Carrier Drive Pinion Cog from the underside and perhaps the short rack gear. 

Edited November 2, 2022 by Ole South
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