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Wild Fandango
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I took photos while I was building my spotlights this year, so I made a little tutorial.

Things you will need:


1/2" PVC coupler. 1/2" non-threaded PVC plug. Wing nut and bolt (I used 1/4-20, you would probably be fine with smaller). LEDs of your choice. You will also need the resistors for the LEDs. This depends entirely on the voltage source you are using. I am using 5v power, so for 3.6v LEDs @ 20 milliamps, it needs 82 ohm resistors.


Some type of clear plastic for your lens. This is 10-year non-yellowing Lexan. You could use acrylic (cheaper) or even something like a CD case or heavy clamshell packaging.


Small rings made of 1/2" PVC pipe. You want them as small as possible without losing strength. I think I got them down to a little over 1/4" wide.

Two pieces of metal tubing for cutting out your lenses and LED holders. Copper pipe would be the best thing to use (retains and carries heat well). I bought "set screw couplings" from the electrical conduit area. Lowes sold singles, Home Depot only sold them in bags, but they were under $4 while copper was all $8 or more. If you have copper pipe on hand already then use that. The main thing is that you want the larger tube to cut a disc big enough to cover the end of the PVC coupling, while the smaller one you want to cut a disc that will fit inside the PVC coupling. I used the 3/4" and 1" set screw couplings, since the measurements are what the inner diameter of the pipe will be, not the actual inner diameter of the coupling itself. Bring the PVC coupling with you to make sure your pieces will fit properly.

"Stabilizer Stake" for narrow sprinkler hoses, found in the sprinkler area of Home Depot for about $3/10 stakes. Depending on how tall you grass is, you may need a taller stake. There are some single piece sprinkler stakes in this area that are about $0.70-$1 apiece.

Adhesives. For final seal, you want a waterproof one. I like Goop. If you can find Marine or Sportsmans Goop, it's more UV resistant, but I can only find regular and Plumbing in my area. For quick gluing, I used 5 minute epoxy. Whatever you use, make sure it's paintable. I used silicone "rainproof" sealant, knowing that it wasn't good for painting, on my first try, but not only did the glued areas not paint, but it contaminated the rest of the spotlight. If you use Liquid Nails, make sure you get the paintable type.



Some kind of heat source to heat up your metal tubing. I used a micro blowtorch like this one from Harbor Freight. You could also carefully use a propane torch or maybe even a cheap clothes iron on high. I tried putting the screws in the oven on 450°F when my torch broke, but it didn't work.

You will also need soldering equipment (heat shrink tubing, etc), wire for power (I used speaker wire but if you want to be really "pro" about it you would need black outdoor low voltage lighting cord), pliers, and clamps big enough to squeeze the PVC plug into the coupler, or a bench vise.


Heat the head of the bolt really well, and press it into the center of the PVC coupler. You want it to be hot enough to let the heat do the work. If you have to use the heat and pressure, you may bend the inside of the coupler. If it stops working, pull it off and reheat it if you can (it may stick if it cools off too much). My blowtorch broke while I was making more. The other way to do this is to use a Forstner drill bit just big enough to put the head of the bolt into. For mine, this required a 1/2" bit, and you must make sure not to drill through the wall of the coupling. Using the heat method makes a hex shaped hole that lowers the chance that the bolt can twist and pop out of the epoxy.


Break it back out once it cools (drop it, use pliers, etc), then epoxy it into place. If it's really too difficult to get it back out, epoxy over it instead, but you risk having it pop back off. If the head of the bolt is very smooth, rough it up really good with sandpaper or wirebrush or a file, or it will pop back off the epoxy. Make sure the epoxy is smeared over the edges of the "underside" of the bolt head (facing the threads), not just underneath it. When you get to the part of the tutorial where you glue the lenses on, you can also put more glue over the bolt


Do this part outside! Take the heat source and the tubing you will use to cut out the LED holder discs with. Heat it up really well, then...


Press it down through the plastic to cut out a disc. Use scrap wood underneath. If the plastic sticks to the cutter, you may want to get a big dowel or something to hold the plastic down through the center of the tube while you pull it off.


When my blowtorch broke, I was able to cut discs with a soldering iron and paperclip instead. I used one of the discs I already made to draw a template with a silver sharpie.


Repeat the process with the clear plastic. With the thick Lexan, the metal tube required constant heat to cut through it and was very difficult. A propane torch might do a better job heating up non-copper material. I first did it with multiple reheats, but then did it by keeping the flame on the metal (up away from the plastic!) while pushing it down. Use bigger pliers than this for that method!
 

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Wild Fandango
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1,494 Posts
Discussion Starter #2

The CD case, however, was quite easy to cut through.


They're not pretty, but as long as the center is clear it'll be fine. You may need tweezers to peel off the protective film.


Mark a pattern on the LED holder discs to put 3 bulbs on. You can modify this tutorial for bigger diameter PVC if you want multiple bulb spotlights. I found that the UV and Red ones should probably have been made with 6 and not 3. The dot pattern here is just a little too close together and had to be spread out a bit. You can use a spare LED (cut the wires off) for better placement.


Heat up a paper clip or needle or put it in a soldering iron and melt holes through the discs. One side of the disc will be flat around the edges, the other side will be rough. Poke through the smooth side, because the side you poke through will be roughed up with melted plastic. You will be putting the LEDs on the rougher side of the disc and want the center area to stay flat. It doesn't matter if the center of the smooth side gets rough, as long as the edges stay flat.


Push the LEDs into the holder. The longer lead/wire is the positive. Put the positive towards the edge of the disc, put the negative one in the center. It doesn't really matter which way it goes, but this keeps things consistent.


Twist the center (negative) wires together cut it short, and solder them together. Cut the positive wires short too, and use needle pliers to bend them over into a little hook. Take the resistors you need and cut one end (it doesn't matter which one) short and curl it into a hook as well. Then loop the hooked ends of the resistors and LEDs together so it looks like the picture above. One of those "extra hands" tools with the clips to hold things together is extremely handy here. If you are good with LED wiring and using a higher voltage like 12v, feel free to calculate how to wire them in a serial pattern with fewer resistors here: http://ledcalc.com


Take your power cord and separate it a bit. Put heat shrink tubing big enough to cover the twisted negative LED wires on the negative part of your cord (positive will be red or have a stripe on it or otherwise be indicated, you usually use the side with no markings at all for negative). Solder the wire onto the center, then push the heat shrink tubing down and shrink it over the center. Then twist the long ends of the resistors together and solder them together, then put heat shrink tubing over the positive side of your cord, solder it to the ends of the resistors, and shrink it again. You just want to make sure it won't short circuit. It's easier to do a good job at sealing up the center/negative group, while covering all the resistors would be difficult.


Push the narrow ring of PVC tubing into the coupler. Use one of the PVC plugs to push it down with a hammer, clamp, vise, or pliers. You want to push it in enough that when you put the LED assembly into it, it's low enough that you can glue the lens on the front. It's better not to have the LEDs directly touching the lens. If your rings are too wide, you will not be able to push them in deep enough. Some PVC couplers have writing around the edge of one end and it will be smooth on the other. Try to remember to use the smooth side, but your glue should be more than enough to overcome this anyway.


Using quick set epoxy, run the wire through the coupler and settle the LED assembly onto the ring. If it keeps popping up, wait for the epoxy to harden just a bit so it's stickier. You may also need to put some very gentle tension on the wire until it holds. Drip more epoxy on top of the edge of the LED disc for maximum strength. If you have trouble doing this, first superglue it in place, then put epoxy on top of the edge. Try to get it as centered as possible.


Drill a hole for the wire in the PVC plugs. If your cable is wide and flat, drill two holes side by side instead of one big hole. You want the hole to be as small as possible while still being able to put the wire through it.
 

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Wild Fandango
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1,494 Posts
Discussion Starter #3

Before pushing it in, put a little of your waterproof sealant/glue on the inside of the plug around the hole so it gets pushed through with the wire.


Push the cap in nearly all the way. We are not making a plumbing connection so you do not need to solvent weld it (unless you already have the cement to do so, in which case go ahead). Simply put a bead of glue around the sides of the PVC cap before pushing it in fully, using a clamp or vise. Do not glue the lenses on first or you will probably rip them back off by trying to clamp it. Then add more glue around the wire, using a toothpick to make sure the hole is filled all the way.


Apply glue around the edge of the lens, or the edge of the PVC coupler. Gently push the lens on until you have a nice seal with the glue. Do not squeeze it so hard that you squeeze all the glue out. Let dry!


On the other end of the wire, I used power plug pigtails from Monoprice.com. Always remember to put heat shrink over the wire before soldering! Small heat shrink over the individual wires, then a larger piece to seal the whole thing. If you accidentally soldered the positive/negative on your LEDs backwards, you can fix that during this step. If your LEDs don't work, this should be the first thing you try to do. The red wire is positive to the center wire of the plug.

(I used the matching female plugs in my power distribution strip. The one I currently have is jury-rigged and not waterproof, so I will be doing a tutorial on a better one when I get around to making it. Right now I just have bare copper wire looped underneath small screws that are screwed into piece of PVC pipe, one row for positive and one row for negative. I then soldered the female power jacks that match the male power plugs onto the heads of the screws and then covered in glue for strength. I have the whole thing inside a plastic box turned upside-down and raised off the ground with yard stakes. For low voltage this isn't a big deal but it isn't all that safe either especially in rain and dew.)


I then spraypainted my spotlight hunter green, but I will probably repaint it black, since the stabilizer stakes are black too. Put the bolt through one of the stake tubing holes, and tighten the wing nut onto it.


Once you push the stake into the ground, you can tilt the spotlight wherever you want it.


So far the green is the brightest one. The blue and white ones are also decent brightness. Next year I will redo the reds with 6 LEDs instead of 3 in a larger diameter spotlight. The violet/UV ones also need more LEDs for better lighting. I have not tried making orange or yellow (amber) ones yet.

Let me know what you think! I know this is last minute but maybe someone can knock a few out over the weekend. These took longer to make than I expected though, mainly due to my blowtorch and soldering iron giving out halfway through the job. I will go back and edit the tutorial based on feedback for clarification. I will probably not get a chance to take more photos until after Halloween, though.
 

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Don't bother with the orange or yellow. Even the superbrights are disapionting. There good for indoor lighting but dont show up very well outside. I used 4 together in a similar setting and it didn't show very well. In the picture, look behind the skelie scarecrow.I have used 8 orange superbrights. nice, but not bright. dsc07371.jpg

Nice in depth tut by the way
 
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