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It is actually the opposite. when you twist clockwise and then put under screw, the screw will splay the wires out thus the stray hanger. When you twist counter clockwise and put under screw the screw will not untwist the wires thus they stay together. Try it someday and watch the action of the wires as you do both. Of course the best method here is to use Stakons. Clean and fail proof. No chance of stray wires unless you miss one putting in the stakon.Originally Posted by Rick Moyer
John T.
Contributor
makes sense- think spiral cut gears, the clockwise rotating screw wants to turn the wire beneath it counterclockwise
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FOUR - CO2 lasers
THREE- make that FOUR now
ONE - vinyl cutter
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[OP]
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In wiring a lamp socket, is it useful to use crimp-on connectors on the ends of the wires? That would be easier than tinning the ends of the wires.
I don't understand how the shape of typical lamp sockets is supposed to accommodate the wires. There is a ridge around the bottom bottom of the socket below the screw terminal so the wire can't sit flush with the surface below the screw terminal.
Contributor
Many lamp sockets do not have the room for a crimp-on connector inside the assembly.
Desk and floor lamps have been wired for over a century with stranded wire without major problems. Well, maybe without problems by many folks.
My lamp socket wiring usually doesn't include tinning the wires. My greenhouse was wired with stranded wire. There are four switches, a dozen outlets and five lamp sockets all done with stranded wire under screw heads and wire nut connections.
It isn't rocket science.
Make it neat and do not over tighten the screws. Also remember to not wrap a wire around a screw terminal with the wire crossing over itself.
To me it seems simple, after all my father had me doing such at about age 8 or so.
jtk
"A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
- Sir Winston Churchill (1874-1965)
Contributor
I once had to take a week long US Navy micro-miniature repair class. The final test was 4 hours to solder 70 connections to NASA standards. The standards were even more rigid as too much solder isn't good either. In the mid-70s, NASA standards required that any strand not touching the element to which it was being soldered had to be coated with solder but still distinguishable as an individual strand.
I agree with you, Shawn. Twist clockwise and solder. Then twist the tinned wire clockwise around screw and tighten. Electronics 40+ years
Ken
So much to learn, so little time.....
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I twist the wires in the same direction they are twisted when made.
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Contributor
This is a simple and effective solution. We use these on machinery that's subject to a lot of vibration and they hold up well. They are thin and crush under the screw but contain the wire strands quite well.
fastenal.com/products/details/0749664?r=~|categoryl1:%22601280%20Electrical%22|~ %20~|categoryl2:%22601347%20Terminals%20and%20Wire %20Connectors%22|~%20~|categoryl3:%22604304%20Ferr ules%22|~%20~|sattr01:^%2212%20AWG%22$|~
Contributor
Good advice. They use stranded wire because stuff on boats moves- even the hull can flex. Stranded wire flexes without cracking. I use heat shrink terminals or add heat shrink over the terminal separately. This not only protects the exposed wires from corrosion, but it also keeps the wire from getting stressed at the join to the terminal.
Member
This is how you do it. No need for any thing else such as soldering or crimping on connectors. I was taught this by an electrician I was working for.
Moderator
All this varied advice points to different ways to achieve the same thing with stranded wire - a connection with good conductivity, strength to not come apart, and a clean connection with no stray strands to cause shorts. Many of us have been making these connections successfully for decades with obviously different techniques.
I found this tutorial on making electrical connections with wires. It looks reasonably good, especially concerning the details of crimping stranded wires.
https://learn.sparkfun.com/tutorials/working-with-wire
This doc from Molex is full of useful information including charts at the end, for those who like to read:
www.mouser.com/ds/2/276/molex-487566.pdf
BTW, my own preference for crimped connections for most stranded wire comes from a military project our group did creating a mobile control and data acquisition monitoring station for field explosives. I wrote all the software and had a hand in the design and implementation. This was in the '80s and the specifications for that project were for crimped connectors on most stranded wire connections. It was explained to us that where wires were subject to movement from either flexing or vibration, soldered stranded wires may break at the point just past where the wire turned solid from the solder. This did not apply to this type of military connector where soldering was required, however the cable connector in this case provided strain relief to keep the wires from moving at the connection:
Soldering-connector.jpg
For standard lamp sockets I have no problem with stripping, twisting tightly, tipping with solder, and tightening the screw firmly. As mentioned in another thread, I'm also a believer of using a dab of dielectric grease on most friction connections, especially those outside or in damp locations (under a trailer, etc.) As with any connection, tug after connecting to be sure it is tight. For connections exposed to the environment, I like to use heat shrink tubing if possible.
Another favorite way to seal connections, is the self-sealing silicon stretch tape, sometimes sold as Rescue Tape:
https://www.amazon.com/Rescue-Tape-R.../dp/B001JT0ET8
This is especially good for larger connections, such as two extension cords plugged together. The tape bonds to itself and makes a great seal. I like to use the clear tape. It will also make temporary repairs on water hoses.
JKJ
Contributor
Why counter clockwise? That seems backwards when every stranded wire I recall using is twisted clockwise from the wire manufacturer.
Member
John Terefenko
Member
Join DateOct 2006LocationNew JerseyPosts939
Originally Posted by Rick Moyer
Interesting. Could you explain why this is better than clockwise? It would seem to me that as one turns the screw, a clockwise twist of the wires would be compressed whereas a counterclockwise twist would want to unravel? I'm just a homeowner so likely there's something I don't understand.
It is actually the opposite. when you twist clockwise and then put under screw, the screw will splay the wires out thus the stray hanger. When you twist counter clockwise and put under screw the screw will not untwist the wires thus they stay together. Try it someday and watch the action of the wires as you do both. Of course the best method here is to use Stakons. Clean and fail proof. No chance of stray wires unless you miss one putting in the stakon.
Contributor
I've never tried it, but I would think the stranded wire would fight being twisted the opposite directed it was twisted at the factory. I deal a fair bit with finely stranded marine wire and I have a heck of a time getting that to stayed twisted in the clockwise position, let alone twisting it completely opposite. I never wrap marine wire around a screw and mostly use crimped terminals with it.
Member
If you crimp then you have no problem. But I suggest you try the counterclockwise twist Just watch the action of the strands and do it both ways. You will never believe me unless you try for yourself. I can not do it for you. Just giving my advice that I have used for many years. I have seen people wrap solid wire around a terminal couterclockwise and now that is wrong.
John T.
Member
Another technique I saw mentioned on SMC (by a retired electrician) is to strip the wire further back, but leave the piece of insulation on the wire. Twist the wire counter-clockwise, then loop the exposed wire clockwise around the screw.
As a clockwise twist of wire strands is compressed, the strands first contacted by the bottom of the screw head will "roll outward" from the screw shaft. If the strands are twisted counter-clockwise, the strands will be forced closer to the screw shaft as they are compressed.
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