Vintage Electrical device

masculinist

I found an old Singer sewing machine. The plug connection, due to its odd shape resembling nothing I had seen before, stumped me until I realised... it's probably meant to be plugged into a light fitting.

How do you guys feel about plugging it in ? Whats the worst that can happen ? My tripswitch trips ? Right ? If it was continuously used could anything worse happen ?

I dont want to damage it from its original condition by changing the plug and I'm not sure if those vintage devices ever had an Earth. I dont think they do.

Are there any adapters which can convert one of those ''light fitting connections'' into a regular plug ? Or is that just a fancy name for a cord with a bayonet fitting on one end and a regular plug on the other end ?

coylemj

The only juice a sewing machine will use is to drive a relatively low power motor, there will be very little risk of it tripping a switch. Anything with a light fitting plug was intended to use no more than a domestic bulb which means max. 100w.

In the days when domestic sockets were scarce (every single one usually required a separate fuse in the fuseboard), it was pretty common for people to have a double adapter fitting in a light socket, then you could plug in a bulb and a low-power mains device like a sewing machine. A lot of the adapters had a cord pull or button to switch off one or both sockets.

You were expected to plug the bulb into the angled socket so that the switch cord (partially shown) would not touch the hot globe.

2011

masculinist wrote: »

How do you guys feel about plugging it in ?

If you have reason to believe that it may not function correctly it may be unsafe. I recommend that you do not plug it in unless you know it is safe to do so and you clearly don't.

Whats the worst that can happen ?

Someone gets seriously injured or worse.

My tripswitch trips ? Right ?

Wrong, it might not trip.
If plugged into a lighting circuit most likely the MCB protecting the circuit is rated at 10 amps. Theoretically a current of just 0.05 amps can kill you.

Don't muck about with a potentially leathal voltage. Don't plug sewing machines into lighting circuits. This carry on is dangerous.

Steve

Before you do anything, cut the bayonet plug off and fit a regular 13A plug with a 3A fuse.

Make sure your sockets have RCD protection.

Personally, I'd run it through a PAT tester first. The insulation could have degraded or moisture got in over the years.

masculinist

Well I actually do have some unused qualifications (level 7 technician) in Electrical Engineering so I'm savvy enough but I'm not an electrician. I went into a different branch of engineering for level 8 and 9 so I have an unusual skillset. I feel comfortable revealing that on this thread. Any other thread and some loon might start an argument about honesty because they think its all a fantasy on here. I understand why some of you are heavy on the warnings because its the real world. You have to be cautious.

I'm going to find a plug in lamp later and test it out, drawing its power from a wall socket. Its in pristine condition and the little motor draws 0.3 Amps if I remember correctly from the plate. I have a feeling that it has never been used since people started to not know what to plug it into.

Steve

At least put a multimeter on it first and see if there is any reading between the motor housing (assuming it's metal) and either of the mains conductors.

masculinist

Well I finally did it and you'll be glad to know , safely . It works perfectly . I'm really glad that I finally got to use one of these plugs . Before now , they were always some figment of old comic books etc .

Steve

Glad you're still alive

Now will you go fit a proper plug top to it?

masculinist

Steve wrote: »

Glad you're still alive

Now will you go fit a proper plug top to it?

Well I sort of feel like snipping off the end and replacing it would be like destroying an antique . Is there any sort of additional adaptor which would effectively deal with the problem ?

masculinist

http://www.ebay.com/bhp/light-socket-outlet

Those things could come in handy for backpackers in situations where you have to help yourself e.g the middle of Russia or somewhere you cant automatically assume the infrastructure will be helpful. I think I'm going to pick one up anyway and bring it on a trip. Since I like to collect tools I dont need


However for the sewing machine, I suppose I'm looking for the opposite of one of those. And does one exist for a three pin British/Irish standard plug ?

Steve

The problem with those, and the reason they are not used anymore is you can plug them in, stick your finger into them and be electrocuted. They aren't safe.

If you want, you can just buy a bayonet fitting in any hardware store and fit a plug to it. I would strongly recommend you don't.

colm_mcm

The bayonet fitting wouldn't have been original. It's also not earthed either.

masculinist

colm_mcm wrote: »

The bayonet fitting wouldn't have been original. It's also not earthed either.

The Bakelite Bayonet 'plug' on the sewing machine definitely looks original to me.
Or maybe you meant something else ?

I definitely hear and am not ignoring all the good advice above to put a regular plug onto it . Especially if I sell it on or give it to someone who doesnt know what they are doing.

colm_mcm

It may be period correct but things didn't really come with plugs attached until the 90s

We had a few of those fittings knocking around the grandmothers house. I'd say they were quite common as were a bewildering combination of hokey looking adaptors!

Stoner

I was looking at an old movie early 1980s. The detective in it had a two pronged thing. He was having lunch and he stuck a prong in either end of a hotdog and plugged it into his desk lamp. Cooked up the hotdog popped it in the bun and off he went.

I looked them up. Couldn't find where to buy one now.

This is the general idea
http://www.instructables.com/id/Extremely-Dangerous-Hot-Dog-Cooker/?ALLSTEPS

Absolutely mad stuff

Iderown

If the sewing machine must be left as it is AND is required to function then maybe the safest option would be to try to find an external isolating 1:1 transformer for use with it. The sort used with gardening power tools would be much too generously rated to use with the Singer. (Everyone in our family is musical - even the sewing machine is a ...... - sorry about that. )

coylemj

masculinist wrote: »

The Bakelite Bayonet 'plug' on the sewing machine definitely looks original to me.
Or maybe you meant something else ?

What poster colm_mcm is telling you is that the light fitting is of the same vintage but it would not have been supplied with the sewing machine. Small appliances came with bare wires up until the mid to late 1980s when consumer legislation was amended to force manufacturers to factory-fit plugs.

So you will not be compromising it's authenticity by taking that fitting off and attaching a standard 13A plug in it's place because when it was purchased new it had no fitting of any kind.

This is not like replacing the face or hands on a Rolex watch, there are thousands of old sewing machines out there, so many that they are reduced to gathering dust as 'bric a brac' on the top shelves in olde worlde pubs. Changing the plug will not make one iota of a difference to it's value.

masculinist

coylemj wrote: »

Small appliances came with bare wires up until the mid to late 1980s when consumer legislation was amended to force manufacturers to factory-fit plugs.

Cheers. I didnt know that. I did wonder at how wonky looking a plug on an Atari I sold on Adverts was. Although the plug on an old Commodore 64 I had seems fiercely moulded and the same grey color as the rest of the power pack.