A Singer 401a and Greasy Terminal Prongs

Hi everyone, I know, long time no talk. I recently got to meet Elizabeth from My Sewing Machine Obsession and that was pretty cool. She mentioned that I hadn't written in a while. Over a year!

I've been busy with work and fixing sewing machines on the side, even making housecalls in Manhattan. If you need repair work done on your machine, are in NYC and/or can bring your machine to me in lower Manhattan, drop a line.

Anyways, a customer brought this Singer 401a to me. She came my way from Peter Lappin's sewing blog. The customer had just purchased the machine from a "reputable" seller online, and the machine had been damaged in shipping, with one spool pin broken off. She asked if I could fix it, I said no problem.

When she arrived with the machine, she mentioned that after five minutes of sewing, the machine would begin to emit a smell. I told her I'd check it out.

Well, never mind the spool pin, I was appalled to see the condition of the machine. So much so that I subsequently looked up the seller. I will not mention him by name, but based on his reputation and self-description, any of us would probably buy a machine from this guy in a heartbeat. He has been working on machines for longer than I've been alive, so I cannot understand how he let these things go.

The first thing I went to do is plug her machine in to uncover the source of the smell, but I stopped dead in my tracks. Check it out:

See that green stuff? Old Singer lubricant (grease) turns that shade of green after many years, I've seen it inside plenty a machine. And here it is on the terminal prongs--not good. Even worse, there was more on the cable:

How to Remove & Re-Install a Tabbed Stop Motion Clamp Washer

In the previous post, we looked at how to remove and re-install the stop motion clamp washer on a potted motor machine. But many other vintage Singers (like the 66, 99, 206, 306 et cetera) will have a different washer, as seen in the photo above. Here's how you tackle that one:

How to Stop the Needlebar from Moving During Bobbin-Winding Mode

When you set your vintage Singer sewing machine into bobbin winding mode, by cranking the stop-motion wheel counterclockwise, the needlebar is supposed to stop running. This is to save unnecessary wear-and-tear on the machine, and prevent you from having to unthread the needle to wind a bobbin.

However, if a few crucial parts of your machine are dirty, the needlebar will continue to move even though you are in bobbin-winding mode. This is easy to fix, and I've made two relevant videos, below, to assist you.

Reader Questions: Rewiring a 99?

All photos in this entry by Azul from California

Azul from California writes,

I was excited to discover your motor rewiring series, but I have a model 99, which does not have the potted motor and does involve a light switch. The motor is mounted on the side, as seen below.

The Difference Between Domestic & Industrial Sewing Machines (or, How Not to Get Swindled on eBay & Craigslist)

Guess which one's the industrial.

There are many eBay and Craigslist sellers selling vintage domestic Singer sewing machines and branding them “heavy duty” or “industrial strength.” Sadly, these sellers are lying in order to fetch higher prices. Beware of these descriptions:

- “Vintage Singer Industrial Strength Sewing Machine”
- “Sews leather!
- “Heavy Duty!”
- “Industrial Grade!”
- "Semi-Industrial!"

Dishonest sellers know that if you put those keywords into any domestic sewing machine ad, naïve people will be fooled and extra money can be made. When I first got into this hobby, I myself was suckered because I didn’t know any better. So now I’m writing this entry to list some facts and prevent future buyers from falling into the same trap.

What’s the difference between a domestic and an industrial sewing machine?

Reader Questions: Eric's Knee-Operated 15-91

All photos in this entry by Eric from Ottawa

Eric from Ottawa writes,

[The 15-91 I recently acquired] looks like it's in great shape, but it doesn't run. It has a knee switch rather than a foot pedal and it looks like the motor controller has failed. 

To test it, I unscrewed the center of the flywheel so there was no load and plugged it in and got nowhere, even with the knee switch in and fully engaged.

Do you think it's worth re-wiring it to use a standard foot pedal like most of the ones I've seen?

Hi Eric, first off, a little about your machine. The chrome rim on the handwheel plus the design on the faceplate, from the little bit of it that we can see in the photo up top, indicate this machine is from the 1930s or early 1940s (assuming those parts are original). The old-school cylindrical Singerlight visible in the photo below also indicates the machine is from that era.

The “J-“ prefix on the serial number plate indicates your machine was made in Singer’s Canadian plant in Quebec.

Secondly, good on you for trying to run the motor with no load, that’s exactly the correct first step to test out a motor.

Hans and the Singer 206, Part 2

Here's Part 2 of Hans from Chicago's questions about his Singer 206.

Is there any type of regular maintenance a 206 requires (oiling?) to care for them?
Of course. Every vintage Singer requires regular oiling at a minimum (click here to learn how to oil your machine), and I always check the wiring and the motor for safety’s sake. You'll also want to check that the belt is properly adjusted.

This machine came with a needle, bobbin and bobbin case, so I believe it is operable. Are there other attachments that are needed/beneficial?
Needed or beneficial for what? Please understand it is impossible to answer vague questions like this.

I have read this machine uses an unusual needle (206x13) and using the wrong one will nick up the bobbin case.

Reader Questions: Hans and the Singer 206, Part 1

Time to answer some reader questions. These photos here were sent to me by reader Hans in Chicago. As he writes,


In a thrift store, my wife bought this Singer model 206. Our six-year-old recently expressed interest in sewing and we were looking for a machine to get her started.

Hi Hans, I really like the 206 and own several. That being said, the 206 wouldn’t be my top choice to teach sewing to a child, for two reasons:

One, the zigzag adds a layer of complexity you could avoid with a straight-stitch model like the 15, 201, 99, 66 or 221.

Two, more significantly, the design of the 206 requires that the entire machine be tilted back on its cabinet-mounted hinges in order to access and change the bobbin. Some 206s are aluminum, rather than the heavier cast-iron, but even with an aluminum model, this process will likely not be easy for a six-year-old child. You’ll also have to ensure they don’t let the machine slam back down on their fingers.

From what I’ve read in the forums, many people teach children to sew using handcrank machines. If you go this route, I think the most economical route to go would be to acquire a cheap model 99 or Spartan and buy an aftermarket handcrank. Jenny at Sew-Classic sells them.

I should also mention that I’m not a skilled seamster and have no experience teaching sewing to either children or adults. If any readers have any experience in this area and can help Hans out with recommendations, please feel free to sound off in the comments.

More to come in Part 2.

The Complete “How to Re-wire a Potted Motor”

If you are arriving at this entry for the first time, this is a comprehensive guide on how to re-wire the potted motors found on vintage Singer 15-91 and 201-2 sewing machines. It is my attempt to walk someone with zero experience through the entire process.

For your convenience, here are links to all 20 entries in the series. This way you can bookmark this page as a Table of Contents and quickly get to the entry you need.

Part A: Skills Building

1: Wire, Wire Stripping and Wire Braiding
Learn about the tools and wiring basics you’ll need to know to re-wire a motor.







2: Tools & Materials Required for Soldering
Learn what equipment you'll need to complete basic wire soldering.

3: Learning to Solder
Learn and practice basic wire soldering.

4: How to Terminate Your Wires
Learn how to create connections for attaching wiring to power terminals.

5: Covering Wire Joints with Heat Shrink Tubing
Learn how to clean up exposed wiring.

6: The Underwriter's Knot
Learn how to tie wiring into a strain-relieving knot.

How to Re-wire a Potted Motor, Part 20: Hooking It All Back Up

Now we’re at the final step to getting your machine back up and running!

Start by sliding your newly-renovated motor onto the shaft.