Introduction: "Simple" Conversion of Metal Lamp to Use Touch Switch

About: I'm an architect by day. I love doing projects by night, both on my own and with my kids

This was intended to be my entry for the weekly switch challenge but it took 3 weeks for the switch i ordered on Amazon to be delivered so I missed the deadline but thought I'd go ahead and post this anyway.

Last summer I bought a chrome metal lamp at a garage sale for 5 bucks.    I really liked the chrome.   It worked fine for a while but after a few months the push button switch died.   Rather than simply replace the switch, which had already been done at least once, I thought this would be the perfect lamp for a touch switch.   with a touch switch you simply touch any metal on the lamp and it'll turn on/ off as well as dim.  since every bit of this lamp is metal, it's a perfect choice.  there are several types of touch switches available.  there is one that you plug into the wall and then plug the lamp into it.   This lamp doesn't have a threaded rod down the middle so the socket wiring is isolated from the body so i wasn't sure if that would work.   There is also a touch sensor socket that you screw in and then screw your bulb into that.   This lamp has the socket recessed in to the base so the screw in socket wouldn't work.  I went with the hard wired switch replacement.

To spice up the lamp I painted the base and the underside of the metal lamp shade.  I'm reasonable certain that the paint shouldn't interfere with the touch sensor but I'm typing this before it's complete so fingers crossed......

Step 1: Supplies / Tools

here's a simple supply list.  this may vary depending on your particular lamp.

Supply List
Lamp
Touch switch
electrical tape
wire nuts
double stick foam tape

Tools:
Wire cutter
wire stripper
pliers
screw driver (if you need to replace the existing socket)

additional supplies that may be required:
replacement socket
18 gauge wire if lamp wiring is bad
replacement felt for underside of lamp base
sacrificial extension cord to use if you need to replace the main power cord.

ORDERING THE SWITCH.
Before you purchase your switch, check what the electrical load will be so you can get the right sized switch.  Some lamps may have a 300 watt halogen bulb or may have multiple bulbs.  If you have a lamp with 3 sockets, each at 100 watts then that's 300 watts total load. Even if your only going to use 60's, you need to size the switch to handle the maximum.  My lamp has a single socket with a maximum rating of 100 watts.   The switch is rated for 200 watts and I don't go any higher than 60 so this will work fine.  Hopefully in the future I'll swap the incandescent for an LED bulb but currently quality dimmable LED bulbs are out of my price range. 

My local big box store didn't have any of these switch's so I ordered it from Amazon. 
http://www.amazon.com/gp/product/B000BQWVE6

This lamp has a shallow base so I initially thought that I'd have to build a base plate to give enough room for the switch, but I was happily surprised that it fit. 

Step 2: Open Up the Lamp Base.

UPLUG THE LAMP!!!!
This should be rather obvious but felt I should say it anyway.

REMOVE THE SHADE, HOOP & BULB
When I do projects like this I prefer to disassemble the lamp as much as possible to keep anything from getting broken.  A little extra care is well worth the effort.  At the very least you should remove the shade, hoop and bulb.   Keep any small pieces in a  container, preferably with a lid, so that you don't loose anything.

 
 

Step 3: Cut the Old Switch


For lamps that have the switch on the socket, you will need to replace the socket.  You can also simply leave the existing switch in place with the lamp turned on and let the touch sensor take over.  Before disconnecting the socket, read the next step about identifying the hot/neutral wires.  Once you've identified your wires then you can replace the socket.

I found a metal plug cover for the existing switch hole.  One of the sensor wires gets attached to the threaded rod which normally runs up the middle of lamps.  This lamp didn't have that so I'm going to use this metal plug cover.  The hole plug should provide good contact between the wire and the base.

With the lamp taken apart we got a break in our weather so I went ahead and painted the lamp base and the shade. I was planning on waiting until spring because our fall weather has been really crappy (I spray paint outside) but then we had a couple nice days which was all the time i needed.  I really dig the chrome so I'm not touching that.   I painted the underside of the shade yellow and the base green.   I'm not sure if i like the green yet so I'm gonna live it for a while.  I may try another color or go back to black.  That's one thing about spray paint is that it's easy to change your mind.   I liked the yellow because normally you don't see it.  it's only when your in the bed looking up that you get that splash of color.




Step 4: Identify the Hot/neutral Wires

There are 2 wires which power a lamp.  the hot and the neutral.  there may be a third which is the ground but most lamps don't have it.

Before you wire up the touch switch your gonna want to identify the hot wire (black) and the neutrals wire(white).  Ground wires are green.  if your power chord goes directly to the socket then you can simply look at the socket to see which is which (see photo)
Technically with a 2 prong ungrounded lamp, you can wire it either way, but I prefer to be professional about it and make sure that the wiring is proper.  Once you know what your looking for, it's very easy and doesn't take any extra time.

IDENTIFY THE HOT/NEUTRAL WIRES.

Electrical code requires that the hot be identified.  If the wires are colored then the hot is the black and the white is the neutral.   Lamp power cords are usually single color paired wire (white, brown, etc).     Look at the wire carefully.  One side will have ribs on it and the other side will be smooth and will probably have markings on it.  The smooth side is the hot and the ribbed side is the neutral.   You can also look at the plug.  the hot is the smaller prong and the neutral is the wider prong.

 At the socket the hot wire connects to the bottom of the bulb and the neutral goes to the bulb screw.  The hot terminal is always the darker color screw (brass) and the neutral is the lighter color (silver).  this hold true with most electrical stuff like outlets, light switch's, etc. 

One trick that I do is that I will put a piece of blue painters tape on the hot wire.


Step 5: My New Rule..."Never Trust Old Wiring"

After I cut the wires and removed the socket and inspected the wires I was really shocked (no pun intended) with how bad it was.  the wires were old and brittle and the insulation was cracked and flaking off.  I'm honestly surprised the lamp worked at all and we weren't electrocuted every time we turned on the lamp.

LIFE IS LIKE A BOX OF CHOCOLATES......YOU NEVER KNOW WHAT YOUR GONNA GET.....
When I removed the socket I got a surprise.  I discovered that there was a lamp socket into which was screwed a plug adapter and into that was a plug in lamp socket.  Most bizarre thing I've ever seen.  No idea why it was like that.  There's no way that's original.  whoever rewired the lamp took the time to solder the connection but then did this at the socket.  From the age of the socket I'm thinking this was done sometime in the 60's and I can only assume that there were drugs involved.  

I think I'll be inspecting any future purchases before plugging them in.   Rewiring a lamp is pretty easy once you've done it a couple times, so my new rule is that if the lamp is old, I'm going to rewire from scratch rather than trust the old wires.   I've got a couple other yard sale lamps in my house that I'll be working on this weekend.
   
Since this lamp is for my son's room, I'm gonna completely rewire this.  lamps are very easy so this is no big deal and is a small price to pay for a little piece of mind.  i wont have to worry about the little guy getting zapped or the house burning down.
At the hardware store I had a choice.  I could get a lamp kit that came with a socked and a power chord for $10 or I could get a extension chord for $1.50 and a socket for $2.50.  Guess which way I went.

Simply cut the end off the extension cord and then feed it thru the lamp.  I'll need to cut the wire to install the sensor switch but it's easier if you feed it thru and connect the socket first.  After feeding it thru I pulled the two wires apart and stripped the ends.  3/4" of exposed wire is all you need.  Really 1/2" is all you need but I prefer 3/4".  You don't want any bare wire sticking out past the wire nut.    Looking at the wire one side was smooth and the other side had ribs.  The replacement socket that I chose came with a black and white wire leads.   the smooth side is the hot so that was wired to the black wire on the socket.   Wire with ribs is the neutral so that went to the white. 

MAKE THE CONNECTION
I've seen on diy shows that when using wire nuts that you don't need to twist the wire together but I don't agree with that.   As a rule whenever connection wires always twist the wires together before capping with a wire nut.   Lamp wire is light gauge braided wire(18 gauge) so you can twist it with your fingers.  If your working with heavy gauge wire like solid house wiring then use pliers to twist the wires and save your fingers.  Make sure that you use the correct wire nut size for the connection.  The finish off, I always wrap the wire nuts with electrical tape for extra protection.  It'll keep the wires from getting pulled out of the wire nut.

Step 6: Wiring the Switch - READ THE INSTRUCTIONS

once you've identified the hot/neutral wires, wiring the touch switch is a pretty straight forward task.  just follow the diagram THAT COMES WITH YOUR SWITCH!.   I learned the hard way that not every switch is wired the same.  What holds true for one does not hold true for another.  I've included wiring diagrams for 3 different switch and the wiring is different for each.

there are 4 wires on the switch.    One wire connects to the lamp body (threaded rod).  One wire connects to the incoming hot.  One goes to the hot from the socket and the other wire connects to the neutral coming in and the socket neutral.

NOTE:   MAKE SURE YOU HAVE THE RIGHT SIZE SWITCH!!!!!
The switch I have, has a maximum rating of 200 watts. This lamp has a single socket rated at 100 watts so this isn't a fine.  I don't use anything bigger than 60 watts but you always want to size to cover the maximum amount.   Some lamps may use a high wattage halogen or it may have multiple sockets, then you want to make sure to get a switch that is properly sized for the loading.  If there are 3 sockets, each at 100 watts, then you need a 300 watt switch.

NOTE TO SELF....READ THE INSTRUCTIONS
Here's where my inner idiot decided to come out and play.   I thought about leaving this part out of the instructable but then decide to just be honest so others can avoid my mistake.   While I was working on the lamp, I was already working on this instructable.   For this step I didn't really like the way the photo of the wiring diagram that came with the switch looked so I jumped on Google and did a quick search and found an image to use that at first glance looked exactly like the diagram for my switch.  Guess which diagram I followed.    I wired up the new switch added a bulb and plugged it in to test if out and confirm my genius.  I already had the beer ready and the snappy comeback for my wife who wanted her kitchen table back.  The moment I plugged in the lamp then I heard this "POP" and then power in my kitchen went out.  After resetting the kitchen circuit breaker I inspected the lamp switch.   I initially couldn't figure out what had happened.  At first I thought i had gotten a bad switch.  I was followed the diagram and was very careful with all the connections and had wrapped everything with electrical tape so it must be the switch....couldn't possibly be me.   Just to confirm that it was the switch and not me I double checked the wiring diagram.  On the downloaded diagram the white wire went to the hot from the socket and the red wire went to the neutrals but on my switch the white goes to the neutrals and the red goes to the socket hot.  Crap.  You can fill in your expletives of choice for what could be heard throughout my house for the next few minutes.  Luckily the kids were outside so they were spared.   I can already here my son.   "Daddy what does $*%*^ mean?".   Dodged that bullet for now but it's only a matter of time.......

SWITCH NUMBER 2.......(expletive, expletive, expletive)
After I fried the first switch, I didn't want to wait another 3 weeks for Amazon so i called around to some hardware stores and found one at the first place I called (Lowes didn't have it but Home Depot did).     This time I read the wiring diagram about a dozen times and checked and rechecked all the connections.    

Step 7: Final Result

Once you have everything wired and you think your finished the only thing left is to test it.  With the second switch I took an extra precaution of plugging into a gfi outlet.    IT WORKED!!!!!!!!    My son loves it, although I have to teach him to not play drums on it because he'll fry the switch in no time.    I was a little worried that the new paint would interfere with the switch but it doesn't.

When I first started I was going to write here about how easy this project is and how you can milk it because others don't know how easy it was.   In the end, what should have been a half hour project took 4 days but it's done.  I'm happy.  My son is happy.  That's all that matters.