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It knocked me right on my

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It knocked me right on my

Post  Admin on Tue May 30, 2017 9:11 pm

About a week ago we got some heavy rain and one of the skylights out in the back porch started leaking. I've since gone up there and painted some roof cement around it. It really needs new flashing as we think the roofers pounded nails through it when we had a new roof put on about 15 years ago. It would leak every once in awhile when we would get an abnormal amount of rain. Anyway, the wood around the skylight was soaked and I wanted to get it dried out as fast as possible. I went and grabbed this 1956 Vornado 16C3-1 that my grandparents bought new. I plugged it in and as soon as the switch clicked on, SMACK! Whoa! One hell of a jolt. I was standing barefoot on a wet floor too. I pulled the plug and went and grabbed my multimeter, I plugged it back in and touched one lead to the metal frame of the fan, and the other to the grounded box of my fused extension cord, sure enough 126vac. I flipped the unpolarized plug around in the receptacle, and took a reading, 0vac. So, somewhere the line is making contact with the frame of the fan. From the outside, neither the power cord nor headwire (the wire that goes from the base to the motor) appeared to be cut or frayed. Probably not the smartest move but I needed to get that wood dried out, so with the plug in the receptacle "the right way", I went ahead and used the fan anyway.

Last night I thought I would see what's up with it. First, I removed the cover from under the base to look at the connections to the switch and the choke coil. I didn't seen anything, nothing was loose and with the choke coil unmounted from the frame of the fan, I was still getting continuity from one side of the power cord to the frame. So, the problem was not in the base. I put it back together and opened up the motor. Sure enough, the insulation on the headwire was cut right where it entered the motor.






I was worried it was a problem with the motor or choke coil. I'd be looking for a parts fan if that was the case.


The original rubber grommet rotted away which exposed the wire to the sharp edge of the motor housing. Plus, the headwire insulation has become hard as a rock.


The motor is caked with oily dust.



I'm going to clean as much dirt off and out of it as I can. Have to be careful not to disturb the rubber parts, especially the rubber motor mounts on the ends of the motor can. It would be really fun coming up with a replacement for those.

They just don't make them like this anymore.

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Re: It knocked me right on my

Post  Cribbs74 on Tue May 30, 2017 10:59 pm

I would replace the cord with new. A grommet to prevent that from happening again should be easy to find. Glad you didn't get hurt.
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Re: It knocked me right on my

Post  RknRusty on Tue May 30, 2017 11:56 pm

Wow, barefoot and wet. I bet that was one helluva jolt.

Once when I was fairly young(thank goodness) I was underneath a couch, laying prone on a slate porch floor, shirtless, wearing short pants, probably sweaty, and got clobbered while plugging something(I don't recall what) into an outlet. That is the worst I have ever been hit. Blew the breaker in the box. Since that time, I have never plugged anything in while barefoot on stone or ground or anything damp or wet. Nor do I allow anyone I see doing so, to proceed without warning them not to. I am sure I would not survive such a shock today. That goes for resetting breakers and other such actions too.
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Re: It knocked me right on my

Post  Oldenginerod on Wed May 31, 2017 3:50 am

I've only been hit by "mains" power once before when installing a fluorescent tube while the switch was on and inadvertently touched a pin on the end.  We have 240vac at 50Htz.  I could nearly count the cycles.

The worst shock I've ever experienced was from a Model T Ford ignition coil.  Those who were involved in youth work back in the 70s are probably familiar with the "Electric Chair" used as a form of "entertainment" and incentive at youth group games nights.  The leaders manuals even had plans for building one.
It was basically a wooden stool with a Model T coil connected to a Big Jim lantern 6V battery.  The high tension side was attached to two square fly-wire pads on the seat. That thing would curl an inch-long spark from one pad to the other when you pressed the button.  You never saw anyone stand up so fast when sat on that thing.  Imagine the public outrage if you used something like that today?   No!

Anyhow, I was trying to repair it one day and had it upside down on my lap.  While fiddling around inside I must have shorted something out and it lit up.  So did I affraid
As my muscles contracted I pulled down hard on the thing, firmly holding the contact pads against my legs.  I couldn't let go and the thing just kept buzzing me.  It's not like a single shock from a normal ignition lead.  This just kept going.  Probably around 30,000 volts.  I eventually (in reality it was probably only 5-6 seconds) managed to push it off my lap and spent the next hour lying down hoping that my heart kept going.  Not a pleasent experience. Warm
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Re: It knocked me right on my

Post  pkrankow on Wed May 31, 2017 7:34 am

That "electric chair" sounds like a couple years ago I discovered when this house was switched from well water to "city" water that the power to the well was cut in the crawl space and dropped onto the ground. This was before I purchased this place. I had the breaker panel replaced, everything that was believed to be a circuit was "on" and I SAT on the live 220v wire in the crawlspace with limited headroom.

OUCH. I burned a hole in my pants with the electric shock.
OUCH. I smashed my head into a joist.
Lucky I missed all the exposed nails.
I wish it was funny. I have a hard time getting more than a wry smile from this incident.

Phil
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Re: It knocked me right on my

Post  Mark Boesen on Wed May 31, 2017 10:18 am

lol, i got the same exact fan, same exact problem!
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Re: It knocked me right on my

Post  GallopingGhostler on Wed May 31, 2017 10:54 am

Admin wrote:I put it back together and opened up the motor. Sure enough, the insulation on the headwire was cut right where it entered the motor.


Yup, aged cord insulation finally broke down for one reason or another. Because the fan case and cage assembly is of metal, to add another level of safety, you could go with a line cord that included a grounding wire, use a 3 prong plug. Connect grounding wire to motor frame. I'd go with a minimum of 16 gauge appliance cord. Install an insulating grommet at the hole. If motor wiring, say, laquer insulation breaks down shorting the windings to frame, then it will pop a circuit breaker. if current is not high enough, then at least shunt current leakage to ground and not to hands.

I'm going to clean as much dirt off and out of it as I can. Have to be careful not to disturb the rubber parts, especially the rubber motor mounts on the ends of the motor can. It would be really fun coming up with a replacement for those. They just don't make them like this anymore.

You might be able to fabricate rubber shock mounts using pieces of automotive fuel line hose, washers of bicycle inner tubes, bits from hardware store special hardware section, etc.

Good luck, I'm sure you'll come up with something that'll do the job. Smoking Wink

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Re: It knocked me right on my

Post  roddie on Wed May 31, 2017 7:50 pm

Man... you are lucky Jacob. Lucky it wasn't an electric heater drawing serious amperage. I'm sure you'll never connect electrical mains while barefoot again..

I've been shocked (on my mouth/lip) by a microphone while playing a band gig.. and let me tell you; it "will" bring a tear to your eye..

Years ago.. I had a boss who showed me.. to place a finger on the metal-panel while resetting a circuit-breaker because electricity will follow the shortest path to ground. It made sense to me then.. and I still do it whenever I switch a breaker.

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Re: It knocked me right on my

Post  Oldenginerod on Wed May 31, 2017 8:03 pm

roddie wrote:
I've been shocked (on my mouth/lip) by a microphone while playing a band gig.. and let me tell you; it "will" bring a tear to your eye..

Roddie. I've had exactly the same experience with a mic. It certainly rattles the confidence a bit.

I remember my dad teaching me when I was young to never hold an electrical appliance while plugging it in. Once switched on he would always brush it with the back of his hand before attempting to grab it. If it was live, it would give you a small jolt and throw your hand away from it. If you grab it first you may not be able to let go. Even with double insulation and residual current devices I still to this day brush a drill etc with the back of my hand. Not a bad habit to have I guess.
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Re: It knocked me right on my

Post  dckrsn on Wed May 31, 2017 8:41 pm

While setting up a Jacob's Ladder a few years ago, a brush
with the secondary, got my attention, and a sore arm. This was
a repurposed neon transformer Scarey stuff. The "blue wire"
on a f96 high output fluorescent ballast(900v) had a similar
effect on me back in the 70s. May explain a few things about me. Rolling Eyes
Bob
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Re: It knocked me right on my

Post  roddie on Wed May 31, 2017 8:56 pm

Oldenginerod wrote:
roddie wrote:
I've been shocked (on my mouth/lip) by a microphone while playing a band gig.. and let me tell you; it "will" bring a tear to your eye..

Roddie.  I've had exactly the same experience with a mic.  It certainly rattles the confidence a bit.

I remember my dad teaching me when I was young to never hold an electrical appliance while plugging it in.  Once switched on he would always brush it with the back of his hand before attempting to grab it.  If it was live, it would give you a small jolt and throw your hand away from it.  If you grab it first you may not be able to let go.  Even with double insulation and residual current devices I still to this day brush a drill etc with the back of my hand.  Not a bad habit to have I guess.

Not a bad habit at all Rod. As for double-insulation.. Black & Decker must have gotten some criticism in the early days of that technology. My brother told me recently that DeWalt is owned by Black & Decker. DeWalt had been an old quality name in power-tools.. and B & D wanted to wanted to increase their market-share.. so they bought the name. I'd say they've done well.
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Re: It knocked me right on my

Post  Admin on Wed May 31, 2017 11:12 pm


Got the motor cleaned up and the old wires removed from the motor leads. I have to be careful with the original motor leads as the insulation is hard and no longer flexible. Replacing that wire is not the easiest, I would have to unwrap the tape from around the coil and carefully remove and reattach a new wire directly to the thin copper winding.

roddie wrote:I'm sure you'll never connect electrical mains while barefoot again.
LOL, I probably will.

First I plugged it in, picked it up and positioned it where I wanted it, and then turned the switch. As soon as that switch clicked on, I felt a tingle in my finger tips, not so much in my feet. We have vinyl tiles out in the porch so I probably wasn't grounded very well, otherwise I probably would've gotten more of a shock. For all I know, fan was like that for awhile and I just wasn't grounded the last several times I used it.

I know some of my tube radios have "tried" to teach me a lesson. Many transformerless "AA5" (All American 5) tube sets have what is called a "hot chassis" where one side of the line cord goes to a capacitor that is directly connected to the chassis (for a floating ground), or in some cases the line cord is connected directly to the chassis. This was originally done for RF noise suppression purposes. Touching any metal part of the radio when grounded can give you a shock. Depending on the placement of the power switch and what way the unpolarized plug is plugged in the receptacle, the metal parts of the radio may be hot when switched off, or hot when switched on. In normal use, the user is expected to only touch the cabinet of the radio and the knobs. Screws on back and bottom and the metal knob stems may be energized. This is why it is important to use an isolation transformer when working on these kinds of sets.

Then there are sets like this:



This is a 1949 Wards Airline 84KR1520B. The cabinet is made entirely of metal. When I first brought this radio home about 15 years ago. I sat it on the workbench out in the garage, and plugged it into a "dim bulb tester" that places an incandescent bulb in series with the radio to limit current in case of an internal short. With the bulb sized right, the radio should operate if no shorts are present. The radio came on and started to tune in stations. The workbench is topped with a 1/4" steel plate. As you could've guessed by now, I got one crazy shock when I reached out and touched the radio while leaning on the bench top.

I think the worst shock I've ever gotten was from an old electric fence charger a friend wanted me to look at. It was a 1940s/50s weed burner that was made for long range and use with large animals. It was made to be hooked up to a 6v battery. When hooked up, you would open the door on it and give this little wheel a flick to get it going. It would sit there and go "click-click" each second as it quickly closes and opens a leaf switch sending out a pulse. You could see the little blue arc between the switch points each time it was opened and closed. After somehow coming in contact with the wingnut on the side of the unit, I couldn't feel my hand for about a day.


Last edited by Admin on Wed May 31, 2017 11:23 pm; edited 6 times in total

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Re: It knocked me right on my

Post  GallopingGhostler on Wed May 31, 2017 11:15 pm

An option may be using two layers of heat shrink tubing to replace existing wire insulation, if that might be easier and do the job.

I had an encounter with the high voltage of a flyback transformer on a 13" black and white Panasonic TV back in the early 1970's while a senior in high school. Don't know the exact voltage, but was somewhere between 10kV and 20kV. With back off and powered up, I got my hand within 2" of the high voltage lead. A several inch long blue arc jumped through the wire insulation to my hand. My arm instinctively jumped back hitting the wall and right on my funny bone.
After that, I had a strong desire to join the Army. Memorial Day

BTW I went Band but scored high in electrical. Back then, questions were more simple. Which one is a light bulb? A) Photo of football; B) Photo of a pipe wrench; C) Photo of a fork; D) Photo of an incandescent light bulb. Rudolph

Nice Octal radio set, Jacob, my father had a similar radio in octal tubes, a Silvertone on AM. I built several kit tube radios in high school, a Graymark 3 tube AM and 80 to 15 meter band regenerative radio using octal plug-in antenna coils to change bands. It used a 35W4 rectifier, 12AT7 twin triode, and 50C5 Pentode audio amp; Philco 5 tube compact Superheterodyne AM table radio, and a 5 tube Superheterodyne Graymark AM and 80 to 20 meter shortwave radio. Alas, I should have kept at least one of the Graymarks instead of giving away. E-Bay had 2 of the Graymark 3-tube, but cost was $300+ for the kits, more than I wanted to pay.

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Re: It knocked me right on my

Post  Admin on Sat Jun 17, 2017 4:24 pm

Here it is with it's new cord! Most Vornado fans originally came with a gray cord, so over a week, I ran to about 6 hardware stores, and an antique lamp shop in search for gray 18/2 zip cord...with no luck. I ended up ordering 100' of this stuff off the internet. It is close to exactly the same color as the gray paint on the fan. It's 18AWG SPT-2 cord so it has thicker insulation, although the fan would've originally came with the thinner STP-1. The thicker insulation should hold up better with the frequent handling and flexing that a portable fan cord would experience. Heat and oil at the motor will probably still do a number on it over time. The motor needed a good cleaning, it runs smoother and cooler now.





Here it is with my little Red Vornado "VFAN Jr." that I bought new last year. It is more powerful than most other fans of the same size that are available today, but the old one runs circles around it.




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Re: It knocked me right on my

Post  getback on Sun Jun 18, 2017 8:16 am

Glad you got her up and running again Jacob, You can clearly see the difference in the motor size and construction of the older fan compared to the new and see why it would blow it away in performance ! There are a couple older fans around here that i refuse to throw out although they didn't work last time i plugged one in Laughing
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Re: It knocked me right on my

Post  GallopingGhostler on Sun Jun 18, 2017 9:16 am

Good going, Jacob. I can see why the older fan would put out more wind. Its got larger blades and a larger motor, plus true venturi styled fan housing with turbofan styled outer ring. Not just a fashion statement, they did things right 70 years ago. Smoking

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