Building a 10 Watt LED Task Lamp w/ 3rd Hand Soldering Holders
Using walnut and 6 mm aluminium w/ a 10 watt LED bulb I create a task lamp for my electronics table that also features a set of third hands.
So starting out, I'm using a thick 2 inch piece of walnut, however if you don't have access to that, you can laminate several pieces together to accomplish this depth. The walnut I'm using measures 5 x 7 x 2 inches.
I want the aluminum to sit inset in the walnut, so I used the xcarve which is a CNC machine to carve out a 1/4 " indention on the top of the walnut.
Once that was done, I flipped the piece over, and designed another section on the xcarve. This area is for housing some electronics for the light.
For the inset I'm working with a thick 1/4 inch piece of aluminum and I'm using a really fine bit to carve out the area I need cut, where the holes need to go. While you could carve all the way through the aluminum, I decided to just scratch the piece to show the areas that needed to be cut and drilled, because it's a lot faster.
So once I had my outline, I cut it up with the bandsaw and then I did a fair amount of sanding on the beltsander to smooth the edges. Next I proceeded to drill out the holes in the corners. So I started with a small drill bit, then got a slightly bigger one, an even bigger one and so on, until I reached the half inch I needed.
For the arms, I'm using 3/8 inch aluminum rods, as well as rods with an interior dimension of 3/8 inch, so one fits within the other. I debated for a while how to design the arms, finally I settled on using small pieces of aluminum rods connected with screws through holes and tightened with wing nuts.
To create this I first need to cut up a whole bunch to size, and I'm doing this on the bandsaw. You can make these any size you'd like, as you're piecing several pieces together to create one arm, I choose to make most sections 3 inches long. And then I need to drill holes in them on each end and it really helps to have the pieces secured in a metal vice here. You can either use a drill press or a drill.
For the ends of the 3rd hands I'm going to attach some alligator clips, so I need to drill some holes down those solid aluminum rods as well. I'm using the drill press for that.
So for the light, I'm going to use a super bright 10 watt LED. I'm going to attach it to a piece of aluminum measuring 2 x 2 inches. I cut this section out on the bandsaw, however you could certainly carve it out on the xcarve. 10 watt LEDs require 30 volts, so I'm going to need a booster to up the voltage.
To hold the light, I have the 2 x 2 inch piece of aluminum. I also have one of the solid rod pieces and I cut a groove using the bandsaw (about 1/4 inch down, cutting a couple of times to accomplish a 1/4 inch depth), and then I'm fitting the square piece into the groove of the rod. To secure it in place I have a screw through with a nut on the other side.
Now on the side of the walnut I need a hole for the power cord and I also want a switch to turn the light on and off. So I'm drawing out the size of the switch, and first I drilled two holes, one for the switch and one for the power cord. Then I'm chiseling out the area for the switch to fit in perfectly.
To connect the arms together, I'm putting a machine screw through the holes I drilled, and then securing that with nylon washers in between. To tighten everything I'm using wing nuts and that way I can adjust whatever angle I need. Then I have some alligator clips that I can fit in the holes drilled in the top aluminum pieces here.
Now time to attach everything together. So I'm mixing up some epoxy and I'm fitting the alligator clips in the rods. And I'm also gluing the aluminum to the walnut.
Ok, so next I'm epoxying in the hollow aluminum into the corners. And I have cut the one on the far left a little shorter, that's for the light. So just carefully gluing them all in. So to connect everything, first I'm tinning a wire with some solder. I'm using a continuity tester to see where to solder the power to on the switch. And then attaching the wire to the switch and soldering it in place.
Now there's a hole drilled through the section where the light will go, so I'm feeding some wires through that. And then I'm connecting them to the booster which will fit into this carved out area.Then I'm attaching the switch through the hole here with some hot glue.
I have a power cord here attached to the booster, so that is going in the second hole I have prepared here. And then gluing the booster down. Now all the electronics are in place.
To get the whole unit off the ground, I'm cutting off some pieces of rubber here to make little feet and hot gluing those on as well. So the wires are coming up through one of the hollow tubes, so I'm just going to test the light here, and it works. It's super bright.
Let's work on the light. The 10 watt LED gets pretty hot so I decided to attach some heatsinks on the backside. I did numerous tests to determine how many heat sinks I needed, and I even anticipated using a small fan which I didn't end up needing. So here I'm cleaning up the metal to prepare the surfaces. To attach the heatsinks to the aluminum I'm using thermal adhesive. So I'm mixing the two tubes together, and putting on a light coat on each heatsink, then it should be clamped so I'm carefully putting on this piece of osage orange because it's pretty heavy.
I let that dry for another, then I turned it around, and glued on the LED light to the other side. So here you can see I have the wires going up through the light part here through holes I've drilled. And I choose to leave these exposed because I thought it looked pretty cool.
Then I'm sanding the edges here to create a light chamfer and then I'm finishing the walnut with some of my tung oil wax polish and it really brings out the color.
Now for the underside, all the electronics are exposed, so I want to add some protection, yet have plenty of air flow, so I picked up some fine wire mesh at the craft store. So cutting to size, and then just attaching with a couple of small screws, and that looks good.
Then finally I'm soldering the light on. Let's plug it in and see if it works.
OK, and you can move the arms around, move the light around, place it wherever you need it. And of course this is really nice to have when you want to hold something in place, for soldering or whatever.