Saturday, April 18, 2015

Rewire Willcox & Gibbs Light Fixture


This light fixture came with the Willcox and Gibbs chain stitch machine I received this week.  It is caked with some unknown crud and the cloth wire insulation is badly worn.  It is time to rewire.


The detents in the female half of the switch enclosure were made to snap into mating holes in the male half.  This connection was never meant to be separated.




To separate the switch enclosure, use a drill bit slightly smaller (I used a 5/64ths bit) than the square detent.  Very carefully drill the detent out taking care to stay in the center of the detent.  We want to end up with a square hole again when finished.  Also be careful not to drill any further into the enclosure than necessary to go through the detent so that the switch isn't damaged.


Use a pick to pry the undrilled corners of the remaining detent upwards while striving to keep from deforming the female outer housing.  This is a little fiddly.  Pry a little, then test, then move to the next hole, pry a little, test... until the halves come apart.


Gently work the two halves apart.


Slide the female half down the wire enough that you can pull the switch assembly from the male half of the enclosure.


Be careful not to destroy the fibrous insulating sleeve inside the male half of the enclosure.
Congratulations, that was the hardest part of this whole ordeal.


Next, pull the shade, wiggling back and forth, from the male half of the enclosure.  There are spring clips underneath that hold the two parts together by friction.  Be careful not to lose the spring clips.


Here you can see the little ball formed in the clip which protrudes through the base of the shade.


Once the switch assembly is removed, the screw terminals can be seen.  This one looks like the person who originally assembled it was new to the idea of a screwdriver.


Here are all of the parts lined up.  Now don't lose anything!


Before going any further, take a few minutes and clean up the detent drillings.  We want the fixture to look as original as possible when finished.


Nicholson makes a small pack of miniature files which contains a tapered square file that is perfect for dressing the holes back to square.



Use a half round file to deburr the inner curved surface.  Go from the square file to the half round file several times until the outside looks square and the inner surface is free from burrs.


Polish all of the brass with a piece of Scotch Brite, then clamp a bit in a pair of needle nosed pliers and do the inside of the lamp socket; don't forget to hit the center tab at the base of the socket.


Use a pick to pry the tab up slightly so that it will make good contact with the lamp.


I use these products to clean, lubricate, and polish bakelite, bare metal, nickel plated metal, and electrical components.


Blow the switch out with compressed air, then spray the internal contacts with contact cleaner. Before the cleaner evaporates, work the switch five to ten times.


Then use a teflon based DRY lubricant on hinged parts.  Dry lubricant won't attract dust and lint.


I clean bakelite parts with Mequiars Cleaner Wax, bare metal and nickel plated parts with Mother's Mag Polish.  If the metal has rust, use 0000 steel wool lubricated with some oil to get down to the nickel.  If the rust has gone through the nickel, it will still be silver.  If the metal is too grimy for polish, I'll hit it with acetone.  If that doesn't work, its time for brake cleaner.  Once the rust, grime, and goo is off, back to the polish.  The final buff is with 100% carnauba wax.  Here are the parts all ready for the new wire and reassembly.


Ordered two feet of black rayon covered 18/2 wire from thestonedoor (seller on ebay) that matched the original lamp wire perfectly.  Pull back the cloth outer sheath a couple of inches exposing the two conductors.


Strip back the insulation about 1.5 inches on each conductor and twist tightly.


Wrap the twisted wire around a 1/8" drill bit and then wrap the wire around itself about one and a half turns and clip the excess.  Smooth the wire so that no loose strands are sticking up.


Brush a little flux on the newly formed wire loop which allows the solder to flow nicely.  Lightly tin the wire all the way to the insulation.  Try to avoid globs.


Using smooth jawed pliers, immediately flatten the loop all the way to the insulation.


Use an awl to round the opening in the loop.


Connect the wires using the original screws.  If using a polarized plug, connect the white wire to the neutral side (the outer section of the socket) and the black wire to the center tab.  It is a good practice to use the black wire as the hot and the white as the neutral and to always run the hot wire through the switch mechanism.


Slide a 1/2" length of heat shrink tubing all the way to the base of the socket to prevent the cloth outer sheath from fraying.  Trim any frays.


As an added layer of protection, cut a strip of electrical tape and lay it on top of the wire in the side grooves and then another around the circumference of the socket.


Slide the socket into the fibrous insulating sleeve and then slide that assembly into the metal male half of the socket enclosure.


Run the female half of the socket up the loose end of the wire.  I wasn't quite sure how I was going to keep the original look of the socket when I started, but upon seeing the series of square knock-outs all the way around the male half of the socket, it immediately became clear that, by aligning the square holes in the female half with the solid sections between the knockouts in the male half, the assembled enclosure would be hardly distinguishable from the original construction.


Clean the mating portions of the socket enclosure halves with rubbing alcohol and lightly sand with 320 grit sandpaper. Then squirt a little clear E6000 glue on a paper towel and get a small amount on the end of a q-tip.


Smear a thin layer on the inside of the female half of the socket.  You don't want the glue to ooze out during assembly.  Keep the glue away from the square holes to avoid unnecessary clean up.


Slide the halves together with the square holes evenly spaced from the switch arm and rotate until the square holes are centered over the solid metal areas.  It looks almost like the original detents.


Making sure to keep the center line of both halves of the socket in line, lightly clamp (a rubber band can also be used) the halves together to prevent them from slipping apart while drying.  Allow the glue to cure overnight.


Add some dry lube to both sides of the spring clips and place them on either side of the metal tube extension, align the hole in the shade with the extruded ball in the clip and push the shade onto the clips.


The extruded ball should present itself through the hole in the shade.


Attach the mounting clips to the metal flange at the base of the thread spool assembly, adjust the light fixture position, and tighten the mounting screw.





I assembled the light fixture to the sewing machine and positioned the cord over to the motor connection bay.  Once I settled on the shape of the cord, the cord was marked at the edge of the connection bay with a piece of painters tape.

Remove the motor mounting screw and have someone hold the motor a few inches above the connection bay.  Hold the tape against the edge of the connection bay and mark where the wire will be cut.  Cut, strip, and twist the wires.  Slide a piece of heat shrink tubing over the cloth sheathing, then wire nut the light cord to the existing motor connections.  I used Ideal gray wire nuts; they are small and just accommodate three pieces of 18 gauge wire.

Carefully lower the motor back into the cradle in the base making sure not to pinch any of the wires and tighten the motor down to the base using the motor mounting screw.


One thing that I didn't think about because I typically restore Singers with the electrical connection from the wall coming first to the machine itself is what would happen when the connection comes first to the foot controller.  Because there is no constant source of power for the light, it works on the same rheostat as the motor which means there is no light until the foot pedal is depressed and full light only when the motor is running faster than I typically sew.  It does give an "old timey" feel to the machine however.

As an option, the cord to the light fixture could be left long, probably 6-9 feet with a separate electrical plug attached and plugged into the wall.  This would allow the light to be on all the time and controlled by the switch on the fixture itself.

The wire that was attached to the light was short and gave me the impression that it was connected at the motor, but I can't say for sure and it doesn't describe it in the manual.

I'm going to leave the light connected to the motor as shown in the above photos because I don't want another long length of cord to deal with when setting up the machine to sew or when packing it away. It will also display better on the shelf.

Hope this helps,
Michael

Disclaimer:
Don't attempt the techniques explained in this article if you don't have electrical experience or are not certified in electronics.  Doing so may result in electrical shock and/or death.  If you decide to act on these techniques, you are doing so at your own risk.  It is recommended to have your work checked by a licensed electrician or certified electronics expert.











Tuesday, April 7, 2015

Sunday, March 29, 2015

Rewiring Vintage Singer Sewing Machine For Polarity

Updated For Clarity May 22, 2023

Vintage Singer sewing machine old style AC plugs were not polarized; consequently the hot side of the circuit can run through either side of the machine.  The light socket can provide a shock even with the light switch off depending on how the non-polarized AC plug is inserted into the AC receptacle.

New AC plugs are polarized so it provides an opportunity to wire the machine in a safer manner.

I am providing a wiring diagram that depicts a polarized wiring path using a polarized AC plug.

It might be helpful to also note that polarity does not matter with regard to the controller and the motor.

I hope you find it useful.
Michael



Disclaimer:
Don't attempt the techniques explained in this article if you don't have electrical experience or are not certified in electronics.  Doing so may result in electrical shock and/or death.  If you decide to act on these techniques, you are doing so at your own risk.  It is recommended to have your work checked by a licensed electrician or certified electronics expert.

Wednesday, March 25, 2015

Rewiring a Cord with Vintage Singer Push-On Connectors



Singer Push-On Connectors
Singer push-on connectors are typically found on Singer cabinets for models 66 and 101 and Singer bentwood cases for models 99 and 128. They usually date from the early 1920's and are found on power cords, motors and foot pedals. They push onto a terminal post.

#190659 Female Connector
This is the female terminal post assembled.  The inner bakelite portion unscrews from the metal outer sleeve.  The ridges in the outer sleeve are actually the threads.  The electrical wire has been removed from these connectors.

These are the component parts of the female connector which consist of: the outer sleeve, the inner receptacle with lug, a fiber or bakelite washer, a brass screw, and a brass washer.

#190658 Male Connector
The male connector screws onto a console and presents the male stud that the female connector pushes onto.


Rewiring a Cord with Singer Push-On Connectors:
Sometimes the outer metal sleeve can be easily removed by holding onto the bakelite insert and simply unscrewing it.  Other times it is stuck pretty good.  

Note also that on the opposite end of the cord, the cardboard insulator has been lost.


If stuck, use AeroKroil to free the threads along with heat from a hair dryer or heat gun (don't overheat which could crack the bakelite).  Lightly tapping on the sleeve and insert will facilitate the oil in penetrating into the threads.  It might take several days of reoiling, tapping, and heating to break the outer sleeve free.  Be gentle and let time do its job... these connectors are exceedingly rare and almost impossible to replace.


As a last resort, place the outer sleeve in a vice with an adaptor made for holding round objects.  Use a pair of pliers with jaw protectors to unscrew the inner portion of the connector from the outer.  It can't be emphasized enough how much care must be taken here not to crush the outer sleeve in the vise or to crack the inner bakelite section with the pliers.



Once the outer sleeve is removed, you will see that the old wire is knotted under the bakelite washer and attached to the center stud via a brass screw and washer.  The screw will be underneath a wrapping of insulating tape.  Sometimes the screw has a thin coating of solder to prevent it from backing out.  Discard the old insulating tape.


It will be necessary to heat the solder to remove it (don't overheat causing the bakelite to melt or come loose from the metal stud.  In the photo above, a desoldering tool is used to suck the molten solder away from the screw and washer.

Clean all of the components inside and out.  You may want to paint the outer sleeves at this point. 


Use 18 gauge 18/2 SPT-1 wire (lamp cord).  The SPT-1 uses a thinner, more pliable, insulation than SPT-2 which makes it easier to tie the knots inside the connector and wall plug.

Separate the wire leads, one for each connector, and pass each lead through the metal sleeve, then the bakelite washer.  Tie a knot in the wire leaving about two inches of wire beyond the knot.  Strip the wire from the knot to the end and hand twist the strands.

Wrap the wire once around an 1/8" drill bit shank and twist the wire twice around itself.  Cut off any remaining wire.

Using solder, tin the loop and the bit of wire back to the insulation.


Using smooth jaw pliers, squeeze the tinned wire and loop flat.  This will make it easier to screw the loop to the lug.



Use an awl to round out the hole in the loop.


Attach the tinned loop to the lug with the screw and washer.  Make certain that the screw is snugged down well.

Adjust the knot so that from the left side of the knot to the right end of the bakelite threads is one inch.


After the knot is adjusted, wrap the area between the bakelite threads and the knot with a few wraps of electrical tape to keep it isolated from the metal outer sleeve.


Slip the bakelite washer and outer sleeve down onto the inner receptacle and screw it back together.
Use a two and one half inch section of heat shrink tubing to keep the wire from separating further during use.

Since the original wall plug end of the cord was still in good shape, and it maintained the vintage appearance of the machine, I decided to reuse it.  Unfortunately, at some point, the cardboard insulator that fit around the metal prongs and covered the electrical connections was lost.

To make a new cardboard insulator, start with a piece of copy paper and press it onto the metal prongs.  Mark the inside edge of the plug by rubbing it first with your finger then highlight the resulting edge with a pencil.  Cut out the pattern with a pair of scissors.  

I decided to use the cardboard from an old shoebox.  Place the pattern on the shoebox and trace the edge of the pattern with a pencil.  Don't forget to mark the slots for the prongs.

Clean up the prong outlines and cut the new insulator from the cardboard.  Place it on the plug end and trim, if necessary, until it fits well.

I used Shoe Goo to fasten the insulator to the plug since it can be easily removed in the future if need be.  I then wiped on some polyurethane to seal the cardboard.

Wax up the ends and polish the brass and there you have it.

I hope this helps,
Michael

Disclaimer:
Don't attempt the techniques explained in this article if you don't have electrical experience or are not certified in electronics.  Doing so may result in electrical shock and/or death.  If you decide to act on these techniques, you are doing so at your own risk.  It is recommended to have your work checked by a licensed electrician or certified electronics expert.