This restoration is a vintage Singer model 15-91… made special by her date of manufacture. The serial number of AG769262 places the date at July 31, 1946. To me, this means two things… First, it was the first production year Singer began making sewing machines following World War 2. Why? Singer stopped sewing machine manufacture between the years 1942 to 1946 to turn it’s immense manufacturing capacity to aid in the war effort. Instead of sewing machines, they made 45 automatic pistols and bomb sights. The second is that it is a “shiny bits” machine. This isn’t any kind of Singer designation specific to the model 15… it’s just my observation that the machine has a lot of chrome bits and pieces. Looking at the machine it wears fancy scroll plates (Egyptian scroll) and a nickel plated ring around the outside rim of the balance wheel, and other shiny bits that just adds something to the machine. It’s fancy!
Cosmetically, it is in very good condition… the decals are in great condition, the paint is in good condition, and there are only a few instances of scratches in the paint. For this reason, I am going for an original finish restoration. Aside from a total disassembly and complete mechanical restoration, the machine will have a detailed cosmetic restoration to preserve the original black paint and erase the wear marks normally seen on these machines. I prefer this because the black Japanned lacquer paint Singer used is extremely durable, extremely black, and worth saving except under all but the worse condition. Even if the paint is missing over small to medium areas over the machine, it can be matched and restored. The few slight paint defects on this machine will be paint matched with a custom mixed shellac based carbon black paint to blend into the original finish and any defects in the decals will be corrected. The machine will be coated with a new coat of shellac and when the new shellac coat has been sanded and polished, the finish will be beautiful.
Mechanically, it is pretty dirty. There is a lot of oil varnish coating the parts, and the resistance from oil varnish in the rotating mechanisms is noticeable. This condition is expected and the reason the machine is due for a complete restoration.
The goal for this restoration is to restore the machine to as close to new condition as I can. What was it like to sew with this machine when it was new? My ultimate goal is to find out, or at least imagine to the greatest extent possible how it sewed and sounded. The only way I can reach this goal is to completely disassemble the machine and ultrasonically clean and wire brush every nut, screw, and every mechanical part in it. The motor must be disassembled, the wires replaced, and all of the plated parts and pieces must be polished. The body of the machine must be deep cleaned, paint chips color matched, decals repaired where needed, and a new coat of shellac applied to stabilize the original finish for many years to come. Will it be mechanically perfect? Yes… every part and piece will be as shiny as new and oiled for smoothness. Will it be cosmetically perfect? No… That’s not the goal of the restoration, it is still the original paint and there will be a blemish if you look close enough to notice it. But it will be a beautiful machine in excellent condition. Then again, even though all of the parts will be restored to like new condition, the machine did not have a hand rubbed shellac finish or polished chrome fittings when new, so in the end you can decide if the machine could look any better.
Let’s get started… here is the machine before the restoration begins…
Looking under the machine, the mechanism is full of oil varnish…
The first step is to disassemble all of the parts, bits, and pieces. The balance wheel and motor are removed, along with the plated parts. The disassembled parts are laid out for cleaning…
A closer look reveals the oil varnish coating the mating surfaces of mating parts… this is where disassembly makes a difference. It allows all of these surfaces to be cleaned and brushed to like new condition.
All of these parts are ultrasonically cleaned, heated in oil to drive off moisture, and wire brushed to “as new” condition.
The Needle bar, presser foot bar, the bobbin hook shaft, and the upper arm shaft are precision parts that rotate or move in bearing bores. The precise fit of these parts is adversely affected by oil varnish and they must be extremely smooth to spin and move as smoothly as possible. For this reason, these parts are polished after wire brushing. Similarly, all of the bearing bores are wire brushed to remove any varnish coating the bores.
The connecting rod is one part that must turn smoothly. It links to the bobbin shaft under the machine and needs to turn very smoothly. Notice the build up of oil varnish on the bearing end of the rod.
For those interested in the details, there are a few parts to look at closer. Some of the assemblies that move in a “fork” mechanism on this machine have small rollers. Easily overlooked, these are usually stuck and slide rather than rotate in operation. These need to be freed to turn smoothly.
Some parts have covers… the bobbin race assembly has a cover plate that hides gunk. This is disassembled and cleaned.
Then there are things you don’t expect. It’s a detail that shows craftsmanship and attention to detail during manufacture. The next picture shows why I think this.
It’s a part of the bobbin case assembly. If you look at the bottom, it is etched by hand… not only the part number, but the person who did this also added “SIMANCO USA”. I can understand etching the part number, but adding the company name and origin? That’s pride of manufacture and attention to detail. Probably his or her full time job!
Next is the balance wheel restoration. Behind the “textolite” gear found on this machine (and the only part that is not metal), there is a spring mechanism to absorb shock. It is often neglected, but it must be free to move to operate properly. Over decades, the mechanism gets sticky from old grease and it must be cleaned. Easy to do, the balance wheel is disassembled, cleaned, and re-lubricated. Performing this step makes a noticeable difference in operation of the machine.
The tension assembly is disassembled, cleaned, and the take up spring is replaced.
With all of the parts cleaned, they are ready for reassembly. They are set aside for now and the next step is the motor restoration.
The “potted motor” found on the 15-91 and the 201-2 are wonderfully durable motors. Unfortunately, they all have the same problem… the main wires are prone to hardening and cracking. So much so that there are quite a few videos and write-ups on the internet describing how to replace these wires… including a comprehensive tutorial on this topic in the blog section of our web site.
The complete restoration of this motor is more involved than other Singer sewing machine motors and fairly complicated. To ensure this motor lasts for the longest time possible (they are not manufactured anywhere today) it will be completely disassembled and cleaned. The commutator will be polished, the motor shaft polished, the brushes reconditioned, and the grease wicks replaced. Because the bobbin winder is integral to the motor housing, it will be restored along with the motor. New wires are soldered to the motor field coil wires using solder sleeves. The solder joint is covered with shrink tubing, and the intersection of the new wires to the field coil is coated with liquid insulation. Designed to insulate and protect wires, this is a precaution to prevent more cracking and isolate the wires to prevent further deterioration. This is shown in the next series of pictures.
With these steps taken, the motor is reassembled and tested. and except for reassembly, this completes the mechanical restoration.
Now for the cosmetic restoration. This starts with a deep cleaning to assess the original shellac coating remaining on the machine. Despite the smooth appearance of the finish, there is a lot of dirt embedded in the finish. After cleaning, the machine looks nice… the paint is generally smooth and the shellac is intact on the sewing bed and over all of the decals.
There is some shellac missing on the sewing arm and on portions of the pillar. These will be restored with the new shellac coat. The body of the machine is coated with a boiled linseed oil and left overnight. Linseed oil is compatible with the shellac and will nourish the finish of the machine in preparation of the new shellac. But first, there are come cosmetic repairs to make on small paint chips.
After wiping off excess linseed oil, the pain chips are touched up with color matching paint. The chips are small and disappear… The best way to see the difference is before on the left… after on the right.
There is only one small defect in the decals… it is on the back of the machine and would be hidden by the light, but there is no better time to correct it.
It’s a small detail and it will blend and vanish under the new shellac.
In preparation for new shellac, the machine is coated with a thin layer of boiled linseed oil. It is then wiped off of the surface. Fortunately, shellac melts shellac and the sole objective for the linseed oil is to nourish the old shellac and “draw” the new shellac into the old… if that makes sense (it works better than I can explain it).
The machine is prepared for spraying by plugging holes with silicone plugs. Several layers will be sprayed to get enough buildup to allow sanding and polishing without fear of polishing down through to the decals.
The machine took four coats on the sewing bed and three coats over the pillar and sewing arm. The machine is allowed to cure for a minimum of four days before sanding and polishing.
After curing, the new finish is progressively wet sanded with different grits of sandpaper. Linseed oil is used as the wetting medium. The first step is sanding with 1000 grit paper, then 1500 grit paper, then 2000 grit paper, then 2500 grit paper, and finally by two rounds of glaze polishing. The second glaze polish is finer than the first. The final finish is smooth and deep black.
All sanding is done by hand and this is the single most labor intensive part of the restoration. I think the outcome is well worth the effort.
Notice the slight green haze in the last picture? This is the shellac coating revealed by the camera flash. Here’s a tip (and I think a great Trivial Pursuit question)… If you want to evaluate the shellac finish on a Singer sewing machine, shine a flashlight close to the surface of the machine and the shellac coat will present itself as a light green hue. Any place this hue is not seen is where the shellac has worn away and the black lacquer paint is exposed… hopefully not over the decals!
The motor housing is not coated with shellac, any paint repairs here are simply paint matched.
The final step in the cosmetic restoration is polishing the chrome plates and shiny bits.
I’ve given up on trying to show before and after pictures for polishing… the camera simply cannot focus on the before and after. After assembly, the polished parts look fantastic and complete the new finish on the machine. Parts not shown, including the rim of the balance wheel, The balance wheel stop motion knob, the bobbin thread winder guide, the presser foot lift lever, the feed dog tension knob, the stitch length lever, the needle bar foot clamp screw, and the rear cover screw are also polished… that’s what makes them shiny bits!
This machine came into the shop without a light…. a Singer model 15 made in 1946 needs a light! A vintage Singer light was added to the machine and wired to the terminal plug.
After the machine is reassembled, the feed dogs, presser foot bar, needle bar depth, and needle timing are adjusted. The upper and lower tension is balanced by test sewing, and the machine is run to allow the parts to reacclimate to each other. Following this “run in”, all of the assemblies are rechecked and if necessary, readjusted.
That’s pretty much it… at least I can’t think of anything else I can add to a restoration… well except for a base for the machine to sit in (so I made one).
As usual, the before and after pictures tell the story.
If you like what you see please visit our Etsy store at https://www.etsy.com/shop/pungoliving, and see this 15-91 and our other restored fine quality vintage sewing machines. As always, If you have any questions or if I can be of any assistance, please contact Lee at Pungoliving@gmail.com.
If you don’t see a machine you love and would appreciate owning a similarly restored quality vintage all metal sewing machine for your sewing room, let us know! We love custom orders and are happy to locate and restore the “perfect” machine for you!
Thanks for reading!