Make: Cable Light Connectors

Original "Connector" In Action

While making my own low voltage cable light fixtures, I searched high and low for a little piece of hardware that would elegantly connect between the suspension cables and the wires down to the lights.

No luck. Everyone wants to sell you a cable lighting kit or, at best, the only “parts” are $40 bare MR-16 halogen lamp fixtures.

No thanks. Until I could figure out a solution, I simply bent a few bits of heavy gauge copper wire and made hangers like the one at right.

It worked OK, but clearly needed to be replaced with a real solution.

The answer?

Finished Connector Installed, Detailed

Spend less than $10 on parts and make my own connectors. Well, $10 on parts and $225 on the tools necessary to solve this particular problem.

What follows is a description of the tools and some photos of the various stages. If you have even the remotest amount of metal working experience, there’ll be nothing new here (and probably lots of opportunities to make fun of me).

But, as pictured at left, I achieved success!



Old, Manufactured, Connector

At left are the two connectors I have from the original set. I liked the general design and wanted to do something similar.

My one complaint is that the set screws that hold the wires in stick out way too much. It looks shoddy.

I decided to use 8-32 threaded hex rod connectors as the basis for my cable connectors. Into these, I found that 6-32 threaded set hex head set screws would likely fit and thumb-screws to fit the hex rod connectors are easy to find.

So, clearly, I was going to need to drill some fairly precise holes, cut threads, and then cut a slot into whatever base material I decide to use. This was turning into a bit of general machining on relatively small parts.

This was going to require tools I do not have.

The Tools

Drill Press

I ended up with a 12″ Ryobi drill press from Home Depot. It isn’t the best press in the world, but it’ll do for the relatively light duty use I’ll get out of it.

Overall, a solid machine. Like the press pictured at right, it includes a set of lasers that create cross hairs on the work area.

This is handy for sighting things in and drilling accurately.

But it isn’t good enough.

As I needed to drill holes pretty close to dead center in the hex rod connectors, I would need some means of holding the things down on the drill table.

Enter the cross-sliding vice.

This rather brilliant little bit of iron works like a standard vise to hold whatever part you need held.

However, the base has two additional cranks that, quite literally, slide the vise around on the X and Y axis.

Thus, you can clamp the cross-slide vise to the drill table, clamp the part you want to machine into the vise, and then use the X/Y axis cranks to exactly position the vise under the drill bit.

I bought the one pictured at right. It works well enough for my needs at this time.

For about $100 more, you can pick pick up a device with considerably more quality of build and precision of movement.

And then they go up from there.

Cutting threads requires a Tap and Die.

I have always wanted a tap and die set. As a 10 to 12 year old, who didn’t spent a half an hour in the nut/bolt or plumbing department of some random hardware store screwing this bit to that bit and dreaming of all the ways the world would be better if everything were threaded?

This was pretty much the ideal started set for my needs. It included the 6-32 and 8-32 taps I would use for this project and, as a bonus, it contains a 1/4″-20 tap and die. 1/4″-20 being the standard sized threads used across all cameras, tripods, and every other device that can mount to same.

They key to success with a tap and die is two-fold, as far as I can tell:

(1) Use oil. A couple of drops on the cutting blade. Go in a full turn, back off a half a turn. Repeat.

(2) Use exactly the right sized drill bit. With the Irwin tap&die set, they provide a list of the exact drill bits that should be used with each. The bits — which can obviously be had from any number of manufacturers — are of “wire gauge” and do not necessarily follow the standard sizes found in, say, your average drill bit kit.

Drilling Hole In Hex Connector

Every drill should come with lasers.

It really does help align the bit with the desired drilling point. I used a punch to make a divot on the piece to keep the bit from scooting off to one side or another.

Besides, lasers are cool.

Like the tap and die, drilling metal will benefit from a little bit of oil on the bit. It makes the bit last longer and keeps the piece being worked cooler.

And heat is more problematic than just a burn risk. Some kinds of metals can be hardened if heated too much while being worked. If this happens, then it is quite easy to, say, break a tap when trying to cut threads in the freshly drilled hole.

In this image, I have already drilled and cut threads in the hole for the set screw. This second hole will be what I would later cut down to using a hack saw to make the cable channel.

Finished Connector

This is the finished and assembled connector ready for use.

I used a hack saw to cut from where the thumbscrew is inserted down to the hole drilled in the previous picture.

I then used a fiberglass cut-off blade in my dremel (a small file or grinder would work fine) to smooth down the channel and make sure the cable would fit.

Finally, I ran the tap through both the length of the hex connector and the hole for the set screw to ensure that both had clean threads.

Finished Connector Next To Original

This is a comparison of the new connector and the old “connector”.

I’m particularly happy with the set screw. It is nearly flush with the surface of the hex connector, yet is very snugly applying pressure to the cable.

Pair of Connectors

Finally, this is what the cable connectors look like once installed.

Not bad!

Of course, I can see things about them that I’ll do better next time.

But the reality is that most people will never see them from closer than about 4 feet and, at that distance, they certainly don’t look like the hacks that they are!



10 Responses to “Make: Cable Light Connectors”

  1. Pierre Bernard says:

    I used crocodile clip. Cheap. Easy.

    On the other end of the (stiff) wire, I used screw terminals stripped of their plastic parts. This makes for minimalist sockets.

    Pierre

  2. bbum says:

    I tried that.

    Worked well enough.

    Looked like crap in comparison to the two machined connectors that I did have.

  3. DIY cable light connectors » Developages - Development and Technology Blog says:

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  4. John C. Randolph says:

    Taps and number drills… Takes me back to my high school summer job.

    One of these years, I’ll build myself a machine shop. Some of those old pre-CNC lathes and mills can be had for surprisingly little money these days, especially the smaller ones.

    -jcr

  5. David says:

    So does the vertical cable (that runs to the lighting fixture) contact the horizontal cable or does the body of the connection (hex nut and set screw) form part of the circuit? In any case, nicely done and definitely an improvement on the copper hook.

  6. bbum says:

    The body of the connection acts as conductor.

  7. DIY cable light connectors | Something to share says:

    [...] Make: Cable Light Connectors [...]

  8. Kevin says:

    Hi Bill – Very cool project. I found it on the Make blog and nearly spit out my drink when I saw your name attached. However, it completely makes sense that you are a contributor to my favorite magazine!!!

    Send me an email, we need to catch up!
    -Kevin

  9. bbum’s weblog-o-mat » Blog Archive » Mason Bees; North American Native Pollinators says:

    [...] drill press — especially one with lasers — definitely makes this particular part of construction go much much [...]

  10. Ingrid says:

    I want to know what kind of cable are you using. I want to know if aircraft cable can be used in cable lighting. Thanks, in advance.

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