How to Re-wire a Potted Motor, Part 3: Learning to Solder

Once you’ve mastered wire stripping and braiding (as shown in Part 1) and understand the tools you’ll need (explained in Part 2), we can get down to actual soldering practice.

First thing I’ll say is, a soldering iron is dangerous. So is a kitchen stove and a steak knife. Because we learn early on to use a stove and a knife with care, we can use them daily without having any accidents. That same care should be taken with a soldering iron. Here are some steps I recommend:

A. Clean up your workspace. The soldering iron needs a dedicated place to rest where nothing else is near it. The tip gets extremely hot and there should be no chance it will accidentally touch anything, either while it is at rest or while you are using it. Remove all obstructions from your work area, leaving only the things you will need to do the job.

B. Carefully arrange the soldering iron’s power cable. The power cable mustn’t be in the way of your work, and the cable must be placed in a way that you will not accidentally catch it, yank it or even burn it with the soldering iron tip. You must also arrange it so that someone walking past you, a cat, a dog, or God forbid a small child is not able to accidentally trip or tug on the cord while you’re using it. Because my power outlet is located inconveniently, I use heavy clamps to weigh the cable down to keep it out of my way.

C. Consider where the soldering iron will rest. Mine does not have an off switch so remains hot the entire time it is plugged in (and for a good deal of time even after it’s unplugged). I use a soldering iron stand to set it down safely. If you do not have one, use the little metal rest that came with it. If none came with it, rig something up, like an empty ashtray or something. It’s not a good idea to just set it on the table.

These steps might seem like a big deal since I’ve dedicated so much ink to them, but these are all simple, easy things to do. It’s no different than basic kitchen safety, where you generally don’t leave a stack of newspapers on top of the stove.

Now let’s get down to soldering.

1. Get your sponge ready.

Wet and wring out the sponge, then place it in your soldering iron stand. If you don’t have a stand, wet an old sponge, squeeze it out and place it on your work surface near your soldering iron. Weigh it down on one end with something heavy, like a brick or a glass bottle filled with water, so it doesn’t move around.

2. Set your wiring in place.

Take one of your stripped-n’-braided wire scraps and clamp it into the Helping Hands, positioning it so that you’ve got good access to the wire joint.

3. Get the solder ready.

Unspool a few inches of solder. You will be applying this with the hand not holding the soldering iron.

4. Clean the soldering tip.

Plug your soldering iron in. Some will take a minute or two to get hot. You can tell when your soldering iron is hot by wiping it on the sponge, it will hiss and steam a bit.

It’s very important to start soldering with a clean, silver-looking tip. If the tip has any brown or black areas, it is dirty and will not transmit heat well. You’ll grow frustrated as you hold the soldering iron against the wiring for what seems like forever, and still the solder will not melt.

Dirty tip / no good.

Clean tip / good. (Not perfectly clean, but clean enough.)

Wipe it well on the sponge to clean it, then dab a bit of solder on the tip. Get rid of any globs by rolling the iron and/or wiping it on the sponge. Here’s a video showing how to clean the tip:



5. Start to solder.

Press the tip of the hot soldering iron against the underside of the wire joint. You don’t have to press hard, just make contact, and if you have done the braiding correctly the wires will not separate.

Depending on the wattage of the soldering iron you have, it may take anywhere from 15 seconds to 2 minutes or longer for the wire to get hot enough to accept the solder. When you suspect the wire is hot enough, touch the tip of the solder to the top of the wire joint, not the soldering iron.

If the wire is hot enough, the solder will begin to melt. Don’t let it melt in goopy globs, let it melt just a little bit at a time by modulating your contact, and you’ll see that the solder liquifies and automatically flows into the wiring, like the wiring is just sucking it in. It’s actually kind of cool to see. Remember that you should still be able to see the individual strands of the wiring, as opposed to covering it all in a silvery goop, once it starts to melt don’t go nuts with it.

Move the soldering iron and the solder, as needed, to different parts of the joint until the joint is entirely silver.

Here’s a video showing the soldering process:



6. Clean the tip again.

After soldering, repeat step #4 and clean your soldering tip again. You should even do the part when you leave solder on it at the end, and store your soldering iron that way. The solder will protect the tip and keep it from oxidizing. If you’re done soldering, don’t forget to unplug the iron.

Give the joint a minute or so to cool off, and then you’re done!

Things to Remember

Many of you will not get this right the first time, which is why we’re practicing on scraps. Soldering is a manual skill that can only be learned through repetition. It’s like driving a car--the first time you drove you were probably terrible at it, but you slowly got better over time by driving around a lot.

It’s important to remember that you can’t get better at driving a car by reading about it or watching videos of other people doing it. You only get better at it by doing it over, and over, and over again as that’s how manual skills work. So re-read these instructions as many times as you need to and practice, practice, practice. If you need more guidance before practicing than I have provided here, go to YouTube and you’ll find tons of videos on how to solder and how to clean soldering iron tips. But the most important thing is to just do it.

Once you’ve gotten this right, there’s just a few more things to cover--wire terminals, heat-shrink tubing--and then we’ll actually get our hands on the machine.

Go on to Part 4: How to Terminate Your Wires

Using my Singer Featherweight 221 to make Sew Mama Sew Holiday Napkins

Here is the tutorial part IV of the Sew Mama Sew Holiday Sew along.

Part IV of the Sew Mama Sew Holiday Sew Along. 

Here are the napkins that I actually did finish before Thanksgiving (and get to use...).  I rolled them up in wooden napkin holders.  Didn't finish, or even get started (except I cut out everything at the same time, so my pieces were ready) piecing together the placemats.  My thoughts were to have the wooden table instead of the tablecloth for my Thanksgiving setting.  Ah well...  life gets in the way, eh?

 This turned out nicely.  Very methodical in doing these napkins. 

This would be a great gift (not these....these are mine LOL) idea for someone for a house warming gift or holiday gift.  

How to Re-wire a Potted Motor, Part 2: Tools/Materials Required for Soldering

You only need the one in the middle

If you can learn to solder, you can breathe new life into that basket-case 15-91 or 201-2 you’ve got with the rotted wiring insulation. If you’ve mastered the wire braiding we went over in Part 1, now you’re ready to try soldering. But before we get to that, I’ll describe the proper tools required, because I don’t want you to overeagerly buy the wrong items first like I did. Read this before you spend any money.

Also consider this: The soldering process requires holding the tip of a soldering iron against your wire joint to heat it, then adding solder. It requires a fairly steady hand--you may have to hold the iron steady for 30 seconds or longer with some precision--so if you have grip issues or arthritis, you may find this challenging; please read the “arthritis” paragraph at the bottom.

Tools and materials you’ll need:



Must-have:

- Soldering iron
- Solder, 63-37
- “Helping Hands”
- Old sponge
- Eye protection

Optional:

- Soldering iron stand
- Respirator

Soldering Iron
Soldering irons come in two different forms, “pencil-” and “gun-” shaped. They also come in different wattages.

After trying out three, I recommend the 40-Watt pencil-style soldering iron. The pencil form factor is easy for me to hold steady, and the wattage is adequate for the task. Radio Shack sells one for $10.99.

The 25-watt pencil soldering iron I bought first is too underpowered. It takes up to two minutes to get the wire hot enough to accept solder.

The 150-watt gun soldering iron I bought second is overkill. It gets very hot very quickly, but is a bit on the heavy side and difficult for me to maneuver, especially when working close to the motor leads.

Solder
Solder comes in a bewildering variety--lead-free, rosin-core, 60/40, 50/50, and in different diameters. What you need is 63-37 Rosin-Core Solder in 0.50” diameter. Radio Shack sells a 1.5 oz spool, which is plenty, for $6.99. (As far as I’ve seen in their stores, that’s the smallest amount they sell.)

“63-37” means it’s 63% tin and 37% lead. This specific percentage is what Singer 221 guru Graham Forsdyke’s motor specialist uses, and he used to work in the Singer factory in Kilbowie, so I’m sure he knows his stuff.

Lead-free solder requires extremely high temperatures to melt, which is why I don’t use it. The other type, rosin-core, melts faster, which is what we want.

“Helping Hands”
You will find this tool invaluable. It’s just two moveable alligator clips attached to a small iron base so it doesn’t move around. When you solder you’ll have the soldering iron in one hand and the solder in the other, so you’ll need something to hold the wires steady, particularly when we get into the actual motor.

I did read about one woman using stacked tunafish cans to sandwich the wires in place while she soldered. I can’t recommend or naysay this method because I’ve never tried it, I’m just throwing it out there.

You should be able to find Helping Hands at your local hardware store or at an art supply store. I bought mine in a local jeweler’s shop in NYC for about $10. There is also a variety for sale on Amazonat cheaper prices, but be sure to read the reviews to avoid the crappy ones that tip over.

Old Sponge
You’ll need an old sponge to periodically wipe the soldering iron tip on while you solder. You’ll also need something to weigh one end of the sponge down, like a brick or a glass bottle filled with water or something. This will all become more clear in the next entry, when we actually get into soldering.

Eye Protection
Chances are slim that something hot will fly up into your eye when you’re soldering, but like most of you, I earn my living with my eyes. If there’s a 0.00001% chance something is going to fly into my eye, I make sure they’re protected. If you don’t already wear glasses, safety glasses are a couple of bucks at a hardware store.

Soldering Iron Stand
I say this is optional because most soldering irons come with a little dinky stand (below) that you can prop the tip on, like a chopsticks rest, to keep from burning your tabletop.

If you’re on a tight budget you can make do without the soldering iron stand and just use the dinky one. But I like using the stand because it’s convenient and has a little place to hold a sponge. I got it at Radio Shack for $8.99. There are also a bunch of these on Amazon.

Respirator
Solder fumes are toxic--it’s gaseous lead--and while a whiff or two probably won’t kill you, breathing it in all the time probably will. If you’re going to solder a lot (as we will for practice), and if you have to do this indoors and you live in a windowless apartment like I do, consider getting a respirator. Otherwise do it next to an open window or if you live in a nicer climate than I do, outdoors.

I bought a respirator years ago because I needed it for various woodworking, sanding and painting projects. I hate wearing it, but I force myself to since I don’t have health insurance. Mine is a model 7501 made by 3M, which comes in different sizes, so I could find one to fit my small face. If you decide you need one, your local hardware store will surely have it. If not, here you go.


For Those with Arthritis
If you have arthritis or grip issues and want to guess if you’ll be able to solder without wasting any money on a soldering iron first, try this. Take the heaviest pair of scissors you own, like a pair of Ginghers or similar. Hold them like a pencil in your main hand, about midway up the scissors. With your other hand, grab a ballpoint pen and hold it like a pen, but up high on the pen. Then touch the tips together, and see if you can keep them touching for about 30 seconds.

It doesn’t have to be exactly point-to-point, but see if you can keep the tips in general contact with each other. This will give you an idea of the manual challenge that soldering demands, and will hopefully help you decide if you’re up to trying it.


Ready?
Thanks for your patience, as I’m sure many of you are eager to jump right into soldering. But if I save even a few of you from wasting money on the wrong soldering iron or wrong type of solder, then I won’t feel like such a dope for blowing my cash on those things.

Next we’ll get to the actual soldering.

Go on to Part 3: Learning to Solder

What I've been doing lately with my Singer Featherweight 221 Sewing Machine-Gaileee

Here is the original Holiday Sew Along post.  http://sewmamasew.com/blog2/2011/10/color-blocks-placemats-napkins-holiday-sew-along/

Here are my pieced placemats, I finally finished today.  I made eight placemats.  Using my Singer Featherweight 221 Sewing Machine.

 I'm going to put the project away though, so I can start my next immediate project.  Making changing table mattress covers, for my DD#2 upcoming baby.  We are giving her my changing table that I used with Grace, and I need to make some new changing covers!  Bought some fabric from Walmart yesterday, and need to treat the fabric (sew the ends, wash, that type of thing), before I can get started.

So this project will be put into some ziplocks with instructions, so that I can tackle the rest of this job later!

<3 Gaileee

How to Re-wire a Potted Motor, Part 1: Wire, Wire Stripping, & Wire Braiding

Singer’s models 15-91 and 201-2 come with beltless, direct-drive motors colloquially called “potted” motors. Sometimes the wiring inside is shot and needs to be replaced; half a century of temperature extremes can rot the insulation away, leaving dangerous bare-metal wires inside an all-metal machine that can transmit a shock to the user.

In this series of entries I’ll teach you to re-wire a potted motor. I’m writing this for people with zero experience, so there are quite a few tools and skills we’ll need to cover. The good news is, you can practice all of these skills without touching your sewing machine, so you can be sure you’ll be able to pull this off before you open your machine up.

Also be aware that you’ll need to acquire a fair amount of tools and materials to re-wire a motor. You or your spouse may already own some. In a nutshell, what we’re ultimately going to need is:

- Wiring
- Wire Strippers/Cutters
- Soldering Iron
- Solder
- “Helping Hands” Tool
- Heat Shrink Insulation
- Heat Gun or cigarette lighter

In addition, you may also need a crimping tool and ring connectors; you'll decide for yourself after we cover how to terminate the wire in a future entry. And don’t worry if you don’t know what some of this stuff is, we’ll eventually get into all of it.

The first things we need to cover are a) the proper type of wiring to use, b) how to “strip” wires, and c) how to braid two wires together.

Types of Wiring

Electrical wiring comes in two types. The first is solid-core, also called single-strand. That’s what a coat hanger is, just one piece of wire. The other kind is called stranded wire because, well, it comes in strands. That’s what we need to use here.

 

Secondly, wiring comes in a variety of metals like silver, aluminum, copper, etc. We need copper wire.

Thirdly, wiring comes in different gauges, or thicknesses. Plumbing pipes come in different thicknesses too, according to the amount of water that will flow through them. Similarly, the wiring gauge or thickness is commensurate with the amount of current they need to safely convey. What we need is 18-gauge wiring, also referred to as AWG-18. (That “AWG” stands for “American Wire Gauge.” Apologies to overseas readers but I am not sure what the foreign equivalents are.)

Lastly, wiring has insulation--also called “jacketing”--that also comes in different thicknesses. The thinnest type is called SPT-1, and that’s what we need to re-wire a motor, or the sewing machine’s light fixture for that matter. SPT-1 wiring typically goes inside of devices, where there will be no abrasion. There is also a thicker jacketing called SPT-2, and that’s what we’d use to re-wire a foot pedal. SPT-2 typically goes outside of machines, where the thicker jacketing means it can stand up to abrasion. I’ll cover foot pedal re-wiring at some future date.

Left: Black 18-gauge wiring (doubled) with SPT-2 jacketing.
Right: Red 18-gauge wiring with SPT-1 jacketing.

The Wiring You Need

You need to buy “Copper-stranded 18-gauge wiring with SPT-1 jacketing.” Don’t deviate. You should be able to walk into any hardware or electrical supply store and find this stuff. It should be cheap, around 10 cents a foot. Buy two different colors. (I prefer red and black, but all that matters is that you can tell one color from another.) To re-wire your average machine you’ll only need a foot or so of each color, but since we’re going to need to practice a lot first, buy five to ten feet of each.

If they’re out of it, please resist the temptation to buy any other kind of wiring. Don’t mess around with electricity. Buy the right thing. You might be tempted to buy 18-gauge wiring with the SPT-2 jacketing, mistakenly thinking thicker is better, but that’s a mistake, as you’ll see in a future entry.

Wire Stripping

Now that you’ve got the right wire, you need to learn how to strip it. This is so you can connect new wiring to existing wiring. So you’ll need to get your hands on a wire stripper.

Wire Stripper Reviews

All wire strippers are not created equal, as I learned the hard way. Please save yourself a few bucks and have a look at this description of three different types of wire strippers. At the bottom I’ll place a video that shows me using each one.

My buddy Jeff can fix anything with practically any tool. He just has that gift, to be able to take the wrong tool and the wrong fastener and just make something work.

I am not my buddy Jeff. I am not a natural handyman and I do not have that gift. My occasional clumsiness means it really pays off for me to use the best tool for the job, to reduce the chances I’ll screw it up. I’ve written these reviews with that in mind.

This is the most common type that you’ll find in every hardware shop. It’s also, in my opinion, a total piece of crap for stripping wires:

It's made by Gardner Bender and I bought it first because it was inexpensive (under $10) and I didn’t know any better. The way a wire stripper works is you squeeze it around the wire at the point where you want to strip off, and the sharp blade cuts into just the insulation, not the copper part.

Then you can pull the insulation off like pulling a sock off of a foot. In theory, anyway.

If you look closely at this tool, you’ll see it’s so poorly made that the holes don’t quite line up. This makes for messy stripping.

However, the Gardner Bender has a cutter at the tip for snipping wires, and also has a part for crimping, which we’ll cover later. So for those two necessary things, it remains useful.

The second one I bought was a Klein Tools Curve wire stripper ($11.52), which seemed more precisely made.

The holes line up correctly.

But I had a hard time using this tool, as you’ll see in the video below, probably because I’m a klutz. The amount of force I needed to apply to strip the wire just seemed unreasonable. I also don’t want to apply that much force to a wire connected to the motor. 

The Klein Tools wire stripper does have a cutter, so at least there’s that. But overall I do not recommend this one, and I would only buy it if it was the only thing I could get.

The third and final tool I bought, and the one that I love, is this “Katapult,” also made by Klein tools:

At $24.65 it’s the most expensive in the bunch, for a reason: It’s designed in a clever way so that when you squeeze the handle, it automatically strips the insulation and slides it off in one easy step. It places almost no stress on the wire, which I like.

One piece of advice if using the Katapult: After you squeeze the tool and it pulls the insulation off, do NOT just release the handle. If you do, the tool will close too quickly and fray the wiring. What you want to do is squeeze the tool, then gently remove the wiring by pulling it to the left before releasing the tool handles. This is really tough to describe or even show in video, you just have to play around with the tool and you’ll see what I mean. So practice on some wire scraps first.

One lame thing about the Katapult is that it does not have a cutter. If you buy only this tool, you’ll still need to buy one of the others to cut the wire. For a cutter, I’d recommend the crappy Gardner Bender because it's cheap and has a cutter and a crimper--though you may not need to crimp, as we’ll cover in a future entry. Alternatively, you can always cut wiring with a pair of tin snips, aviation shears, or EMT shears, if you have any of those handy.

Here’s the video of what it looks like to use all three of these:

You should be able to find at least some of these tools at your local hardware store. I like to support my local businesses, but for those of you who live out in the sticks, or if your stores don’t carry these things,you can order them from Amazon:







Full Disclosure: I should mention again that if you purchase these tools through these links, Amazon sends me a few cents for sending you their way, as I have signed up for their affiliate program. That does not mean I am urging you to buy things you don’t need so I can make a profit. Feel free to ignore these links! I include them in the event that you do need to mail-order the tool and would like to support this blog.

Furthermore, for those who do wish to support the blog, if you buy anything at all on Amazon (like books or whatever), if you first go to Amazon by clicking the link at the top of this page, they’ll also send me a few cents on that purchase. The price is the same for you whether you go through here or go directly to Amazon, they don’t charge you any extra. But please remember that this blog will always be free and you’re not obligated to click anything. I’m not in this for the money, but I wanted to set up a way to make it possible that a few extra bucks might roll in.

Wire Braiding

Once you’ve gotten good at stripping wires, you’ll have to practice braiding them. Braiding is how you’ll connect new wiring to old wiring in preparation for soldering. When we finally get inside the motor you’ll see you don’t have a lot of room to play around in there, so it’s imperative to practice braiding wires first by using scrap wiring.

Start off by stripping about 3/4” of insulation off the end of a wire.

Then grab it between your thumb and finger and twist, twist, twist.

It should look like this:

This reduces the chances you’re going to have frayed wire strands, which we want to avoid because it causes problems later.

Then strip another piece of wire and braid that one too.

Next, cross the two wires at the midpoints.

Then, braid those two wires together. It should look something like this:

It’s trickier than it looks, at least for me, as my fingers always feel too big. But just keep practicing, practicing, practicing, and eventually you’ll get good at it.

Your first goal should be to braid two wires together tightly enough that when you pull on them gently, they do not come apart. I recommend starting with two 3/4” lengths of exposed wire, or even 1” if you’re clumsy, to get the hang of it.

Then, once you’ve mastered that, start using shorter lengths of stripped wire. Your end goal is to get it down to about 1/2” of exposed wire that you can cleanly braid together.

Once you can consistently braid 1/2” of wiring together nice and tightly, you’ll be ready to move on to soldering, which we’ll get to next.

As you practice braiding each piece, don’t throw those pieces away! Even the crappy ones, save them. Cut each side off so that you’ve got your braid in the middle, and about two inches of insulation on either side. We’re going to use those pieces to practice soldering on.

Go on to Part 2: Tools & Materials for Soldering

More Updates Soon, and Send Me Craigslist Photos to ID!

Have you gotten any better at ID’ing Singers from Craigslist photos? I hope so, as it can really pay off. Case in point: I’m selling a 201 to an acquaintance, and she needs a table for it. I started cruising Craigslist looking for cheap sewing machine tables/cabinets to buy, and came across this one for $30 (cheap for the NYC area):

I immediately recognized it as a 206, Singer’s first zigzag. At 30 bucks I couldn’t pass it up, so I went the next day and fetched the machine. Not a bad deal; I've got a table for my buyer and scooped up a great machine in the process. 

So how could I tell it was a 206?
 

The giveaways that this was a 206

Model 206s are not easy to come by, and the ad was a week old by the time I stumbled on it. If the person had put “Singer 206” at the top of their ad, I’m sure the machine would’ve been long gone. 

If you need help ID’ing a Singer from a crappy photo, e-mail me a photo or a link to the ad, and I’ll identify it for you if I can. (I’ll post those photos and explanations here, but don't worry, I won't post the link to the ad if you're worried about competition from other buyers.) You can e-mail me at:

vintage (dot) singers (dot) nyc (at) gmail (dot) com 

Due to popular demand, I’ve been working on tutorials for how to re-wire a potted motor, like you’d find on a model 15-91 and a 201-2. Because I’m writing it up “… For Dummies” style, it is going to be long. I am aiming this tutorial at people who have zero electrical experience, so there’s quite a lot of information and tips I need to convey, and even reviews of different tools you can do the job with. Please be patient and I'll starting posting the multi-part series soon. 

In the meantime, feel free to send those Craigslist photos if you need help.