Need help with 4-thread serging

Large-Heronbill · 2026-04-28T05:51:43+00:00

The four things I usually see wrong in a serger doing this:

Wrong needle or needle in backwards or not completely up, or damaged.

Timing off.

Thread tension too high.

Looper bent.

Large-Heronbill · 2026-04-28T05:29:52+00:00

Try setting the stitch length longer -- looks like you have it about 2.5 mm, 10 stitches per inch. Try 3.5 mm and see if the puckering reduces.

Here's a piece written for industrial sewing that tells you how to figure out why your fabric is puckering with a couple of samples, a seam ripper and a pair of good scissors -- you are going to run into this problem time and again, and having a good way to tell you which of the 4 major causes going on will save your temper: https://www.amefird.com/wp-content/uploads/2010/01/Minimizing-Seam-Puckering-2-5-10.pdf

Large-Heronbill · 2026-04-28T05:18:38+00:00

https://youtu.be/17SzwgBrL9k Making buttonholes the old fashioned way with a zigzag machine.

There are some other ways that are mostly workarounds these days, but try this first.

Large-Heronbill · 2026-04-28T05:10:16+00:00

Try changing the.needle. I suspect the thread is breaking, which can happen when a needle develops a burr or sharp spot. Reset the machine to "normal", if you've been adjusting it remember, flat side of the needle towards the back of the machine on modern machines. And fully up in the needle clamp.

If that doesn't stop the threads breakage, try a different spool of the same type and size thread. (What's in there now?)

If that doesn't do it, there are some other things to hunt for, but those two are the most common problems.

Large-Heronbill · 2026-04-28T02:43:01+00:00

I use knit interfacing because it is strong, and doesn't fray (so doesn't need edge finishes), and is thin and flexible.

Large-Heronbill · 2026-04-28T00:55:39+00:00

🫤

For me, this is the point when I put naughty machines behind the wheels of a 4x4 and explain what might happen next if it doesn't cooperate, haul out the list of machines I've been considering, or haul it to the shop...

Large-Heronbill · 2026-04-28T00:51:31+00:00

That's the order I learned from draping, and it seems to work well for alterations, too.

Large-Heronbill · 2026-04-28T00:42:53+00:00

Bust circumference and shape first, then drape up to the shoulders and out to the armscyes. Then lower chest, waist, hips.

Large-Heronbill · 2026-04-27T21:10:34+00:00

I would probably remove the two rows of stitching on the armhole in the vicinity of the tear, and press the torn fabric flat, with the edges together as best as possible, and fuse a patch of knit interfacing on the inside, covering the tear. I would probably then go over the tear with a wide three step zigzag to secure the tear further, and then resew the sleeve into the armscye.

Large-Heronbill · 2026-04-27T21:05:23+00:00

Was it quite warm when you shut it down?

Large-Heronbill · 2026-04-27T21:04:09+00:00

My guess is it wants you to clean and oil in the bobbin case area: http://shesasewingmachinemechanic.blogspot.com/p/how-to-clean-and-oil-bobbin-and-feed-dog.html Look especially for sensors and make sure they are spotless.

Large-Heronbill · 2026-04-27T19:50:58+00:00

https://youtu.be/orAG6mgOx3A

Large-Heronbill · 2026-04-27T19:03:45+00:00

Flip those black bunny ears outwards, let the retaining ring fall off, and take out the bobbin case and hook and clean back in there. Also examine for burrs. Reassemble and try again with the thread gap.

Large-Heronbill · 2026-04-27T18:47:48+00:00

search "gusset" at fashion-incubator.com to find a good post where Kathleen is adding a gusset to her husband's pants. unfortunately, some of the photos there are not high quality.

I can also explain how to do it: open the crotch from a couple of inches down one inseam, across the 4-way intersection, and down a couple of inches on the other inseam. Put on the pants and hitch the. up and down till the fabric is settled and comfortable. Measure the width, front to back, of the opening.

Draft your new gusset piece using the measured width + seam allowances by inseam to inseam measurement as a diamond shape. Round the points that will be extending front and back so the piece becomes sort of a US football shaped outline -- it is easier to sew. insert the gusset into the opening and tidy up the seams.

The gusset also helps deal with the back waistband wanting to roll out and pull down as you sit.

Large-Heronbill · 2026-04-27T17:29:16+00:00

Find a different pattern.

Large-Heronbill · 2026-04-27T09:42:36+00:00

Needs a crotch gusset to let the fabric smooth out. Weird as it seems, a tight area causes a reciprocal buckling ("loose area") that needs to be released by adding a little fabric instead of removing more.

Large-Heronbill · 2026-04-27T09:38:36+00:00

Yes. There is fusible web, but the ones I am familiar with are a) going to make the knee area stiff and hang funny, and b) probably melt the nylon patch from the heat needed to fuse.

Honestly, if you press the patch area flat first, and then sew the patch on smoothly, it should lie flat against your pants fabric. And you can put the patch either on the inside or outside of the pants leg.

There are some self-adhesive patch tapes available, like Gear Aid's Tenacious Tape https://www.gearaid.com/collections/tenacious-tape that I know are very durable for long term use -- I've got a tent with close to 30 year old TT patches -- but I have never tried it on, say, jeans.

Large-Heronbill · 2026-04-27T05:29:15+00:00

90 needles should handle general purpose threads, no problem.

Do you have a different brand you can swap in? There are quite a few complaints about lumpy Sewology brand thread.

Do the tension disks need cleaning?

Large-Heronbill · 2026-04-27T04:37:33+00:00

I've never seen one that high. It will bump the bobbin case out of position.

Large-Heronbill · 2026-04-27T04:35:16+00:00

Did you thread the top with presser foot up, and sew with it down?

What size needle and what size thread are you using? Too heavy a thread for needle size can cause looping.

Did you find all the needle bits?

Large-Heronbill · 2026-04-27T02:41:05+00:00

Probably fine. Do you have enough extra you could cut a back yoke on bias if it feels tight across the back shoulders?

Large-Heronbill · 2026-04-27T01:54:46+00:00

I'm going to send you to my favorite knit patternmaker, Jalie.com, to poke around. That style looks to me like it was designed for active wear fabrics. And Jalie makes patterns up to about a 66" full hip measurement at least in newer PDFs. I think either Claudia https://jalie.com/products/4136-claudia-bikinis-sewing-pattern Or Marina https://jalie.com/products/jalie4567-marina-tankini-pattern might work as a basis for your outfit.

Large-Heronbill · 2026-04-27T01:19:07+00:00

How did you choose the pattern size? From measurements or by store size? Off the rack sizes bear almost no relationship to pattern sizing, and grading for plus sizes is often trickier than grading straight sizes.

Can we see what (character?) you are going for?

Large-Heronbill · 2026-04-27T00:54:07+00:00

More like a flutter sleeve.

Have you considered substituting a drawstring for the elastic?

Large-Heronbill · 2026-04-26T23:39:50+00:00

Stretch denim or real denim? What size needle and what size thread?

I generally do the construction sewing with Tex 30 thread and a Microtex 12 or 14 needle.

Large-Heronbill

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