Singer’s models 15-91 too 201-2 come upward amongst beltless, direct-drive motors colloquially called “potted” motors. Sometimes the wiring within is shot too needs to locomote replaced; one-half a century of temperature extremes tin rot the insulation away, leaving unsafe bare-metal wires within an all-metal machine that tin transmit a daze to the user.
In this serial of entries I’ll instruct y'all to re-wire a potted motor. I’m writing this for people amongst nix experience, hence at that topographic point are quite a few tools too skills we’ll take to cover. The practiced word is, y'all tin exercise all of these skills without touching your sewing machine, hence y'all tin locomote certain you’ll locomote able to push clit this off earlier y'all opened upward your machine up.
Also locomote aware that you’ll take to acquire a fair sum of tools too materials to re-wire a motor. You or your husband may already ain some. In a nutshell, what we’re ultimately going to take is:
- Wiring
- Wire Strippers/Cutters
- Soldering Iron
- Solder
- “Helping Hands” Tool
- Heat Shrink Insulation
- Heat Gun or cigarette lighter
In addition, y'all may also take a crimping tool too band connectors; you'll determine for yourself after nosotros encompass how to terminate the wire inwards a hereafter entry. And don’t worry if y'all don’t know what some of this stuff is, we’ll eventually acquire into all of it.
The commencement things nosotros take to encompass are a) the proper type of wiring to use, b) how to “strip” wires, too c) how to braid ii wires together.
Types of Wiring
Electrical wiring comes inwards ii types. The commencement is solid-core, also called single-strand. That’s what a coat hanger is, but 1 slice of wire. The other sort is called stranded wire because, well, it comes inwards strands. That’s what nosotros take to role here.
Thirdly, wiring comes inwards unlike gauges, or thicknesses. Plumbing pipes come upward inwards unlike thicknesses too, according to the sum of H2O that volition menses through them. Similarly, the wiring approximate or thickness is commensurate amongst the sum of electrical flow they take to safely convey. What nosotros take is 18-gauge wiring, also referred to every bit AWG-18. (That “AWG” stands for “American Wire Gauge.” Apologies to overseas readers but I am non certain what the unusual equivalents are.)
Lastly, wiring has insulation--also called “jacketing”--that also comes inwards unlike thicknesses. The thinnest type is called SPT-1, too that’s what nosotros take to re-wire a motor, or the sewing machine’s lite fixture for that matter. SPT-1 wiring typically goes within of devices, where at that topographic point volition locomote no abrasion. There is also a thicker jacketing called SPT-2, too that’s what we’d role to re-wire a pes pedal. SPT-2 typically goes exterior of machines, where the thicker jacketing agency it tin stand upward up to abrasion. I’ll encompass pes pedal re-wiring at some hereafter date.
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| Left: Black 18-gauge wiring (doubled) amongst SPT-2 jacketing. Right: Red 18-gauge wiring amongst SPT-1 jacketing. |
You take to purchase “Copper-stranded 18-gauge wiring amongst SPT-1 jacketing.” Don’t deviate. You should locomote able to walk into whatever hardware or electrical render store too discovery this stuff. It should locomote cheap, roughly 10 cents a foot. Buy ii unlike colors. (I prefer blood-red too black, but all that matters is that y'all tin nation 1 color from another.) To re-wire your average machine you’ll solely take a pes or hence of each color, but since we’re going to take to exercise a lot first, purchase v to 10 feet of each.
If they’re out of it, delight resist the temptation to purchase whatever other sort of wiring. Don’t mess roughly amongst electricity. Buy the right thing. You mightiness locomote tempted to purchase 18-gauge wiring amongst the SPT-2 jacketing, mistakenly thinking thicker is better, but that’s a mistake, every bit you’ll come across inwards a hereafter entry.
Wire Stripping
Now that you’ve got the right wire, y'all take to larn how to strip it. This is hence y'all tin connect novel wiring to existing wiring. So you’ll take to acquire your hands on a wire stripper.
Wire Stripper Reviews
All wire strippers are non created equal, every bit I learned the difficult way. Please relieve yourself a few bucks too receive got a await at this description of 3 unlike types of wire strippers. At the bottom I’ll house a video that shows me using each one.
My buddy Jeff tin create anything amongst practically whatever tool. He but has that gift, to locomote able to receive got the incorrect tool too the incorrect fastener too but brand something work.
I am non my buddy Jeff. I am non a natural handyman too I do non receive got that gift. My occasional clumsiness agency it actually pays off for me to role the best tool for the job, to trim the chances I’ll screw it up. I’ve written these reviews amongst that inwards mind.
This is the most mutual type that you’ll discovery inwards every hardware shop. It’s also, inwards my opinion, a total slice of crap for stripping wires:
It's made yesteryear Gardner Bender too I bought it commencement because it was inexpensive (under $10) too I didn’t know whatever better. The way a wire stripper industrial plant is y'all mash it roughly the wire at the squall for where y'all desire to strip off, too the abrupt blade cuts into but the insulation, non the copper part.
Then y'all tin push clit the insulation off similar pulling a sock off of a foot. In theory, anyway.
If y'all await closely at this tool, you’ll come across it’s hence 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, too also has a business office for crimping, which we’ll encompass later. So for those ii necessary things, it remains useful.
The minute 1 I bought was a Klein Tools Curve wire stripper ($11.52), which seemed to a greater extent than exactly made.
The holes line upward correctly.
But I had a difficult fourth dimension using this tool, every bit you’ll come across inwards the video below, likely because I’m a klutz. The sum of strength I needed to apply to strip the wire but seemed unreasonable. I also don’t desire to apply that much strength to a wire connected to the motor.
The Klein Tools wire stripper does receive got a cutter, hence at to the lowest degree there’s that. But overall I do non recommend this one, too I would solely purchase it if it was the solely thing I could get.
The tertiary too in conclusion tool I bought, too the 1 that I love, is this “Katapult,” also made yesteryear Klein tools:
At $24.65 it’s the most expensive inwards the bunch, for a reason: It’s designed inwards a clever way hence that when y'all mash the handle, it automatically strips the insulation too slides it off inwards 1 slowly step. It places almost no stress on the wire, which I like.
One slice of advice if using the Katapult: After y'all mash the tool too it pulls the insulation off, do NOT but unloosen the handle. If y'all do, the tool volition unopen every bit good rapidly too fray the wiring. What y'all desire to do is mash the tool, hence gently take the wiring yesteryear pulling it to the left earlier releasing the tool handles. This is actually tough to line or fifty-fifty demo inwards video, y'all but receive got to play roughly amongst the tool too you’ll come across what I mean. So exercise on some wire scraps first.
One lame thing virtually the Katapult is that it does non receive got a cutter. If y'all purchase solely this tool, you’ll yet take to purchase 1 of the others to cutting the wire. For a cutter, I’d recommend the crappy Gardner Bender because it's inexpensive too has a cutter too a crimper--though y'all may non take to crimp, every bit we’ll encompass inwards a hereafter entry. Alternatively, y'all tin ever cutting wiring amongst a dyad of tin snips, aviation shears, or EMT shears, if y'all receive got whatever of those handy.
Here’s the video of what it looks similar to role all 3 of these:
You should locomote able to discovery at to the lowest degree some of these tools at your local hardware store. I similar to back upward my local businesses, but for those of y'all who alive out inwards the sticks, or if your stores don’t comport these things,you tin guild them from Amazon:
Full Disclosure: I should lift 1 time to a greater extent than that if y'all purchase these tools through these links, Amazon sends me a few cents for sending y'all their way, every bit I receive got signed upward for their affiliate program. That does non hateful I am urging y'all to purchase things y'all don’t take hence I tin brand a profit. Feel costless to ignore these links! I include them inwards the resultant that y'all do take to mail-order the tool too would similar to back upward this blog.
Furthermore, for those who do wishing to back upward the blog, if y'all purchase anything at all on Amazon (like books or whatever), if y'all commencement become to Amazon yesteryear clicking the link at the top of this page, they’ll also shipping me a few cents on that purchase. The cost is the same for y'all whether y'all become through hither or become straight to Amazon, they don’t accuse y'all whatever extra. But delight squall back that this weblog volition ever locomote costless too you’re non obligated to click anything. I’m non inwards this for the money, but I wanted to laid upward a way to acquire inwards possible that a few extra bucks mightiness ringlet in.
Wire Braiding
Once you’ve gotten practiced at stripping wires, you’ll receive got to exercise braiding them. Braiding is how you’ll connect novel wiring to former wiring inwards training for soldering. When nosotros finally acquire within the motor you’ll come across y'all don’t receive got a lot of room to play roughly inwards there, hence it’s imperative to exercise braiding wires commencement yesteryear using chip wiring.
Start off yesteryear stripping virtually 3/4” of insulation off the terminate of a wire.
Then select direct keep of it betwixt your pollex too finger too twist, twist, twist.
It should await similar this:
This reduces the chances you’re going to receive got frayed wire strands, which nosotros desire to avoid because it causes problems later.
Then strip some other slice of wire too braid that 1 too.
Next, cross the ii wires at the midpoints.
Then, braid those ii wires together. It should await something similar this:
It’s trickier than it looks, at to the lowest degree for me, every bit my fingers ever experience every bit good big. But but give-up the ghost along practicing, practicing, practicing, too eventually you’ll acquire practiced at it.
Your commencement finish should locomote to braid ii wires together tightly plenty that when y'all push clit on them gently, they do non come upward apart. I recommend starting amongst ii 3/4” lengths of exposed wire, or fifty-fifty 1” if you’re clumsy, to acquire the hang of it.
Then, 1 time you’ve mastered that, start using shorter lengths of stripped wire. Your terminate finish is to acquire it downwards to virtually 1/2” of exposed wire that y'all tin cleanly braid together.
Once y'all tin consistently braid 1/2” of wiring together squeamish too tightly, you’ll locomote ready to motion on to soldering, which we’ll acquire to next.
As y'all exercise braiding each piece, don’t throw those pieces away! Even the crappy ones, relieve them. Cut each side off hence that you’ve got your braid inwards the middle, too virtually ii inches of insulation on either side. We’re going to role those pieces to exercise soldering on.
Go on to Part 2: Tools & Materials for Soldering
