stillclock

this 401 is testing my patience beyond measure.

cleaned, oiled, singer needle inserted, carefully threaded...

sews along okay until the upper thread breaks. and forget any of the special stitches.

i may just capitulate and take it in, even though i bought it with the express intention of learning how to care for it.

right now i just want it to work properly

aileen

Rodney

Take a deep breath, grab a beverage of your choice and walk away. A fresh mind will do wonders. If it's sewing even a little bit, it means you're close. It's going to be some little detail that's easily overlooked at this point. Others here will probably have your answer.
Rodney

Candace

Have you tried changing out your bobbin? Sometimes a burr or sharp edge can cut the thread.

stillclock

it's as if the thread is getting stuck in the tensioner. i am terrified to touch that mechanism....

aileen

Candace

It may be dirty or have a sharp edge or burr...Take photos so you know how to put it back together. No problem. There are also tensioner diagrams either here or on the net. You won't break it and I thought you bought it to learn (prod) (prod).

oldsewnsew

you might try running some waxed dental floss through it and see if it's hanging on anything there.Does it break at the tensioner, or at the needle? How even are the stitches top vs. bottom until it breaks? Does the fabric (cotton?) pucker or lie flat? Has it ever run correctly since you've had it? If so, then it's probably something simple. Ohh, does the needle plate have any burrs in the hole? Have you tried hand turning it and watching closely underneath to see if you can see the thread catching? All just my 2c worth of detective roleplaying. Forgive me, if you're way past all of it.

miriam

I always take the tension apart and put it back together - easy peasy. Just take your time. Look at a diagram. You can enlarge the diagram and that will help. Usually that is enough to fix the problem. You may have to adjust the bobbin tension as well. I think Tammy has covered that somewhere - dig around her profile or look in an adjuster's manual - possibly it is in the owner's manual anyway. I have one Singer 401 machine that has an issue with the spring on the bobbin case holder. It doesn't want to let the thread pass through right. The machine sews fine on regular stitch but makes tunnels when it zzs or does fancy stitches. It will need to be addressed some time when I have a manual, time and courage. We all have our battles. LOL

J Miller

Here is something I tried with a cranky top tension one time. I took some very heavy button hole and carpet thread that was too rotten to use for anything, coated it with polishing compound from my Dremel tool kit and ran that through and around the tensions. The tensions were gummy and this did help.
Later I did what Miriam always suggests, take it off the machine, take it apart, and thoroughly clean in. Then reassemble and adjust.
All was well after that.

Miriam, that spring around the bobbin case has a spec value. Get a set of small gap gauges, look in the 'swing arm repair manual' and reset it. I've had to do both my 500s cos they were way out. Our 401 was/is OK.

Joe

miriam

Thanks Joe - I know it most likely is the cuplrit since I took a working tension off a machine and put it on. Same problem. Then I put a working bobbin case in it and same problem. Everything else seems ok. But that thing seems a bit too snug with the thread. I think I replaced a spring once but it's been a few years and my old brain can't remember it so well. I think it was not that hard but a PITB.

Jeanette Frantz

You know what I use to clean my tensions? I take my server and sew a chain on it. Then take the chain and ron it through and around all the tensions. For one thing, if it's stray linet, the serger chain will pick it up and for another, it will pick up any thread which might be stuck in the tension assembly. Additionally, by pulling the serger chain through the tensions, you should be able to tell whether you've got a burr or two around that area which would cause your thread to break! JMHO! Hope something works for you.

Jeanette