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Articulating arm Answered

I'm trying to find some solution for an articulating arm to go into an LED lamp project. I'd like either something cheap or something I can build, but so far I haven't had much luck. I could always dismantle an existing lamp, but it sort of defeats the purpose to buy a working lamp and take it apart to make another lamp. Any suggestions?



7 years ago

What I did for my garage work lamp is this, hopefully will be writing an instructable on it soon:

For the arm:

2x 4ft length 1.25" sch40 PVC
1x 1/2"x5" bolt, matching lock-nut and washers
1x 1/4"x4.5" bolt, matching lock-nut and washers

For the base:

10" length 2x4 section
I used some angle iron that was already on my ceiling

For the lamp:

Halogen work lamp

All holes should be about 2" from the end of the PVC section

Drill a 1/2" hole through the center of the base-wood
Drill a 1/2" hole through one end of the first piece of PVC
Drill a 1/4" hole through the other end of the first piece of PVC
Drill a 1/4" hole through each end of the second piece of PVC

Mount the base-wood to the angle iron using the 1/2" bolt.
Mount the first piece of PVC to the base-wood on that same 1/2" bolt.
Mount the second piece of PVC to the other end of the first piece of PVC.
Mount your work light to the other end of the second piece of PVC.

I am currently working on building another brace (or re-brace my angle iron) because it flexes due to lack of stability.

The PVC allows flexing for just enough drop to clear my garage door and garage door opener :)

How about looking for an articulating arm lamp at a thrift store (salvation army, etc.)? If you live near Berkeley, California, there's a non-profit place called Urban Ore, that sells all kinds of stuff and parts for cheap from deconstruction and various donations.


11 years ago

you could try thin pvc pipe.. that way you have all of the different connectors readily available.. and it would have a good friction fit.

But missing the hinge joint of an adjustable arm. Unless you know of a plumbing fitting I haven't seen?

Here's a quick model of what I was thinking-

PVC hinge.jpg

Not a lot of friction there, unless you shim the joint or add some kind of a bolt or screw. And, at the price that fittings are going for, an old lamp may be cheaper : )

Here's a picture of what I've done so far. I'm using two 18" aluminum rods, .25" diameter. I've epoxied some spacers to the ends. There's a #10-24 screw that goes through the spacers, and a rubber washer will go along the screw between the spacers. A wing-nut will provide the compression. I don't know if the epoxy will be strong enough, but the materials are cheap enough to mess around with.


Looks Great!

You could use friction-based joints instead of springs. Use a wing-nut and bolt for adjusting how much force it takes to move the joint.

The same sort of thing had occurred to me, but I'm not sure if that's something you can buy, or something to make. I was thinking of possible scaling down the sort of design that microphone booms use or something similar. If you were making one, you'd have a plastic or metal boom, but what would you use inside the friction joint? A washer or something? How would you connect the arm to the rotating washer in the friction piece? Maybe some thick metal washers sandwiched in with some rubber washers, all clamped together with a bolt through the middle.

Personally, I'd use wood, but that's what I'm used to. Just a bolt in a hole on the ends of the sticks should work if it's not very heavy, tighten or loosen the wing-nut for more or less friction.