Singer 29 -4 Skipping Stiches

[goatiemon]

good day

l'm a tinker, love to fix things, and pretty good with sewing machines of all sorts

but this is my first time playing with a patcher....

now l know these machines are old and "obsolete" and l would have been better off with 29k etc

but l like this one and it is what l have

and hope one of the knowledgeable folk on here can help me out

any way the machine is fairly new to me

and l used it with out learning any thing about it for a while

sewing mostly canvas

(patching military tents)

the stitches were a little close together, and the foot didnt lift as high as l wanted it to

but it sewed through everything l threw at it

till l tried to repair a friends work boots

l was sewing through a couple of layers of leather and foam

so now the stitches were really tiny and l had to help the foot move the work

then there was a clunk and the needle broke

so l replaced the needle

and lo -- it wouldnt sew any more

so l started looking closely at the mechanism

discovered that the foot lifter was set up all wrong (and not lifting)

that the side -to-side adjustment device on the end of the needle bar was frozen as close to the shuttle as it could go

that the ball-end spring on the shuttle carrier was broken

that the thread tension spring (on the needle bar) was broken

and that the shuttle point seemed to be blunted (just the tiniest bit)

and the bobbin thread spring had a deep grove worn under it

so l set the lifter up properly

unstuck the needle adjuster

replaced the springs

(l got them form horseandharness.com)

and ordered their "repair manual" as well as a shuttle

the shuttle is the wrong shape -- that is, the shuttle point is too long, so it never goes into position to grab the thread

(and the manual while a nice compendium of old manuals, is hardly a repair manual and a little pricy)

unfortunately none of that solved the problem....

(well l figured out how to regulate stitch length and foot height)

it sews fairly well through canvas and denim (still skips stitches especially on turns)

and thin leather (with a somewhat over sized needle)

btu even two layers of leather skip

and thicker things skip to the point were they arnt even held together

my best guess is that the needle bar bushings are worn out

i.e. there is too much lateral play

so the needle gets pushed aside by the thicker material so the shuttle hook misses the thread = no stich

l measured the (needle bar) "wiggle"

by poking a buisness card with the tip of the needle at the extremes of the lateral movement

and the holes are a little more than a cm apart

which should translate to even more possibility of movement down by the hook...

so...

is my hypothesis reasonable?

would some one with a 29-4 please measure their needle bar wiggle for comparison?

other thoughts/things to check?

the obvious possibility is the timing....?

which as l understand it isnt adjustable

(except by replacing the cam wheel and roller l suppose)

also the needle seems to go too deep

the short (pick up) grove on the needle is well below the point of the hook (when the hook is supposed to be grabbing the thread loop)

l tried using a shortened needle so that it lined up "right" but that didnt help

could that be a timing problem too -- the needle isnt raising enough to make a good thread loop

perhaps because the cam wheel is worn out?

thanks for your time

this got kinda long

(trying to be detailed -- l'm a little frustrated can you tell)

any way thanks in advance

goat

[amuckart]

1331774571[/url]' post='239410']

the stitches were a little close together, and the foot didnt lift as high as l wanted it to

but it sewed through everything l threw at it

till l tried to repair a friends work boots

l was sewing through a couple of layers of leather and foam

so now the stitches were really tiny and l had to help the foot move the work

then there was a clunk and the needle broke

so l replaced the needle

and lo -- it wouldnt sew any more

As soon as you start "helping" the work feed you're likely to deflect the needle and make it strike the needle plate and break.

Where did you get the new needle? What system and size is it?

discovered that the foot lifter was set up all wrong (and not lifting)

that the side -to-side adjustment device on the end of the needle bar was frozen as close to the shuttle as it could go

By this do you mean the adjuster for foot lift height that is on the presser foot spring on the back of the machine? There isn't any adjustment on the needle bar of these machines that I've ever seen.

that the ball-end spring on the shuttle carrier was broken

that the thread tension spring (on the needle bar) was broken

and that the shuttle point seemed to be blunted (just the tiniest bit)

and the bobbin thread spring had a deep grove worn under it

so l set the lifter up properly

unstuck the needle adjuster

replaced the springs

(l got them form horseandharness.com)

and ordered their "repair manual" as well as a shuttle

the shuttle is the wrong shape -- that is, the shuttle point is too long, so it never goes into position to grab the thread

Do you have pictures of the old and new shuttles? It's likely that the old one was too short, and the only reason it sewed at all was a compatible lot of wear.

it sews fairly well through canvas and denim (still skips stitches especially on turns)and thin leather (with a somewhat over sized needle)

btu even two layers of leather skip

and thicker things skip to the point were they arnt even held together

That sounds pretty symptomatic of a worn out machine. If you hold the wheel still, how much vertical play in the needle bar is there? There should be very very little or none. If there is the roller bearing at the back of the rocker arm is probably worn, or the groove it runs in in the cam track in the drive wheel is worn.

Likewise if you hold the wheel still, is there slop in the shuttle carrier? If there is the rack and pinion under the machine are probably worn out.

my best guess is that the needle bar bushings are worn outi.e. there is too much lateral play

so the needle gets pushed aside by the thicker material so the shuttle hook misses the thread = no stich

I'm not sure what you mean by needle bar bushings, but I think it's more likely that the mechanisms that drive the needle height and the shuttle position are worn and there's enough slop in them that the additional resistance posed to the needle by thicker or harder material is throwing the timing out.

l measured the (needle bar) "wiggle"

by poking a buisness card with the tip of the needle at the extremes of the lateral movement

and the holes are a little more than a cm apart

Can you post a picture of this? I can't comprehend how that's possible unless the whole head of the machine is loose on the end of the arm or it's completely missing something.

Or do you mean mm instead of cm? Even a mm seems like an absurd amount of slop to have in the needle bar. What bit are you holding on to when you wiggle the needle bar from side to side?

Cheers.

[Wizcrafts]

1. The machine is a hundred years old and is probably shot
2. Did you replace the thread check paddle spring in the needle bar? A worn, loose or broken spring causes skipped stitches.
3. Revolve the top throat plate sideways and remove the bobbin case. See how much rotational slack there is in the gears driving the shuttle.
4. If there is excessive slack, the screw that secures the little pinion gear to the shuttle may be loose. You can access this tiny set screw by rotating the machine until the screw hole is visible through a cutout in the back side of the nose of the arm. Once the screw lines up with that hole you can insert a jewelers' screwdriver and try to tighten it up.
5. It's possible that the rack gears under the arm have teeth chipped off, or it has jumped, or been mis-adjusted so that the shuttle gear is out of its normal rotational range. This might explain it not positioning the point behind the needle.
6. The needle sitting too low could be caused by a broken needle shank stuck high up inside the needle mounting bracket. An overtightened securing screw can break a brittle needle at the point above the screw.

Edited March 15, 2012 by Wizcrafts

[goatiemon]

thanks for the quick replies

amuckart your are right l meant mm not cm

big diference

l have abunch of new needles that came with the machine

they are labled 136 x 16, and 135 x17 with various sizes and points for different materials

they also say DPx17 (16) and are groz beckert brand

l meant that the presser foot spring and lifter lever and such werent put together properly so it wasnt lifting

and the needle size slide adjuster thing on the needle bar was stuck with teh needle as close to the shuttle as possible

the shuttles are extremely different l'll get a pic and measurement

wizcrafts

l did replace the needle bar mounted thread tension spring

the rack gears are not broken

and the alinement hasnt changed since the machine worked fine...

(the presser foot wast set up, and l didnt know how to adjust stitch length, but it made every stitch through whatever material)

l took thte needle clamp /lateral adjuster piece off

so no broken needle bit,

and l shortened a needle (with a grinder on the base of the needle)

so that it appeared to line up correctly

and that didnt help

l'll check the shuttle slop, and vertical needle bar play

and get a pic of the shuttles

thanks again

goat

Edited March 16, 2012 by goatiemon

[goatiemon]

so l attached a photo if the shuttles

it's not that easy to see in the photo but the new one (bottom) is about 1.5mm longer and the point shape is different

it is also much bigger around, to the point that it is hard to get out of the machine

but it is probably a moot point because the back lash from wear in the gears is considerable nearly 2mm

wizcraft l cant find the set screw hole you are talking about?

and even worse the vertical play in the needle bar is about 1mm

so the fixing looks like it will involve metal work

l figure l'll bore out the end of the driving lever (trussed arm across the top) and put in a sleeve

any idea what sort of tolerance l should shot for with the slip fit?

there is play in the roller bearing/cam wheel interface too, about a mm

not sure what to do about the shuttle gears with luck the set screw is loose....

perhaps l'll try the needle bar /driving lever sleeve thing and see if that "solves the problem" for now

oh and the needle bar bushing l'm talkign about is part number 8573 pic here:

goat

[tnawrot2]

Just because the needles came with the machine, doesn't mean that they are the right size. I looked up needles for a 29-4 and it didn't state any size you listed.

[Wizcrafts]

A Singer patcher is designed to use series 29x3 and 29x4 needles.

[CowboyBob]

The 135x16 & 17 will still work in this machine.

To get to that screw,there's a square hole on the end the the arm,you need to take a flaslight & look in there as you turn the machine slowly you'll see it & go in the hole w/a small screwdriver to check if it's tight.

Bob

[Skygypsy]

I am havin a similar problem with my patchers now. I have a few one short arm and two long arms. The problem only seems to show or affect the top of the work. I am trying to show a picture on here too but it Sew’s very even neat stitches and with no real cause or anything o predict it it seems to leave a big loop out and then carries on again as normal..... any elp greatly appreciated...PB 

if it works the second picture is the underside of the work...

 

[Constabulary]

looks like a tension issue or the thread is occasionally hanging somewhere. Check you thread patch and how the thread is coming off the spool.

Post some pictures of your threaded machine please. It also could be that the check spring on the needle bar is worn.

Edited January 20, 2019 by Constabulary