If you have any improvements that you like to be made note of, please leave a comment!
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I give you one of the world's largest, DIY LED.
Step 1: Table of Contents
--soldering/electronic knowledge (Must know how to read schematic, but if you cannot, please ask questions by leaving a comment)
--Wood work (need to be able to use the following: lathe, coping saw, various sanders, drills, etc)
--Resin Casting (This was my first real time casting anything, so don't worry about it)
I have broken this instructable up into the following:
--Forming the Wooden LED: steps 2-10
--Making a Mold of the Wooden LED: steps 11-12
--Electronics: steps 13-16
--Casting the LED: steps 17-20
--Finishing Up: steps 21-23
Step 2: Materials for the Wooden LED
various lathe tools
Chisel (or some tool to scrape off glue)
Radial Arm Saw (or some other way of cutting up the pine board)
Putty Knife (optional, but nice)
1" x 6" x 8' piece of pine
Safety Glasses (necessary), ear protection (highly recommended), Respirator (highly recommended, especially while sanding)
Step 3: Cut the Board
Step 4: Glue the Wood
Spread a thin layer (don't just slather it on thickly!) of glue on both sides of each sawdust-free (this is important) board and clamp them together. Have a dry run before you glue the wood, put the worst pieces of wood either in the middle or on the outside (middle so it's hidden, outside so that it'll be turned down into sawdust). Put down paper so you won't get glue on your clamps and/or workspace.
Also, all wood is warped, since all of these segments are from the same board they should all bow the same way. Make note of this while clamping, have all of the pieces of wood bow the same way so that there will be a smaller gap in between segments, thus creating a stronger, cleaner joint.
Once the Glue is dry, scrape off as much excess glue as possible; the glue is harder than the wood and will dull your lathe tools faster.
Step 5: Mount it on the lathe
If this is your first time using a lathe, you should probably read a tutorial somewhere; I believe the lathe is a very safe tool, but can turn very deadly if you don't know what you are doing.
Draw an X on each end of the block of wood to find a crude center.
This Block of wood was too big for my lathe, so I (well, my dad) had to cut off some of the corners (wood that would have been turned down anyways, I didn't take off any useful wood).
Step 6: Turn it Down
Once turned down, take your ruler and mark off a 14cm section; this will be the overall length of the LED. From the left of that section, mark off 2cm and 10cm.
See picture for what each part is for.
Step 7: Carve it into an LED
When you're done sand it down with some fine grit sandpaper and put some finishing wax on, I'm not sure if it's necessary, I just did.
Step 8: Cut and Sand the Nubs
Apply more wax to the newly sanded parts.
Step 9: Find the Center and Drill
Now we have to find the center so that we can drill 2 holes equidistant to it for the legs of the LED. This is probably not too necessary (because you won't be covering the base in silicone later, unlike me). Instead of following steps 9 and 10 you could just drill a hole in the vague center and insert a dowel rod (to give it support while creating the mold)
To find the center of a circle you need a ruler and a right triangle. Draw a random triangle into the base of the led and find the center of each line. Using the right triangle, draw a line that is the perpendicular bisector of each of the triangle's sides. They should all converge to a central point which is the center of the circumscribed circle, the LED. Geometry class actually helped in a real life situation! Who would have thought?
Now that you have found the center, draw in the diameter. Drill 2 (5/16) holes along the diameter, each 1.5cm away from the center.
Step 10: Create LED legs/support
Using super glue (or any other good strong glue), glue the tubes into the wooded LED.
You are now done with all of the wood work, yay!
Step 11: Making the Mold
Go down to a store such as Home Depot or Lowes (I went to Lowes) and pick up a 4 pack of Silicone Caulk. Along with this you need about 5ml of Glycerol (I had 10mL). Supposedly this makes the Silicon caulk better for making a mold (I found this info here), and I used 2.5ml of glycerin per canister of caulk (about 10.1 fluid ounces).
Make sure you mix the silicone and the glycerin well! Slather it onto the wooden LED. I also sealed the base, but later this only caused more headache, so I recommend not putting any silicone on the bottom. Also, make sure you put enough silicone on the lip (it's easy to only put a thin layer there, which will rip later, like mine did)
I made the complete mold in 2 layers, using 1 can per layer.
WARNING: This stuff smells really, really bad (imagine a vinegar smell that's like 100x more powerful and burns your eyes and throat). Use with proper ventilation.
Step 12: Extracting the Wooden LED
Step 13: Electronics Parts
Electrical Components Needed:
(1x) 555 timer
(1x) 0.1uF capacitor (usually ceramic)
(1x) 100k ohm linear potentiometer
(1x) knob for the potentiometer
(1x) 33k ohm resistor
(6x) 10 ohm resistor (1/4 watt or better)
(1x) 3.3k ohm resistor
(1x) 510 ohm resistor
(1x) 0.25 inch knob
(3x) 1 watt white LEDs (usually these come on a star PCB)
(1x) switch (should come with the lamp you are using for a base)
(1x) npn transistor (I used a 2n4401)
(1x) diode (I used a 1n4148)
NOTE: resistor values can be changed, just be relatively close to the values I give (except the 10 ohm resistors, don't use any other values)
Step 14: LED Driver
I'm going to assume you know how to solder. If not instructables offers a large array of how-to soldering instructables.
I personally soldered in the air (not using a circuit board/prefboard) simply because I didn't feel like cutting out a prefboard and mapping out where all of the leads go.
Step 15: Mounting the LEDs
I've also included some pictures of 1 (just one!) LED on.
Step 16: Drill and Glue the Tubes
When the wire is fed through, using the thermal glue again, glue the tubes to the base of the aluminum that the LEDs are glued to.
I added more glue later because the original amount wasn't enough to keep it sturdy.
Feed one wire through per tube.
Step 17: Materials for casting the LED
--about 5.6 ml of catalast (or 120 drops, I measured measured how many ml were in 10 drops and I went from there.)
--drill and a paddle or just a wooden stirrer (drill is so much easier and faster and safer)
--a way of holding the mold and the LED module
Step 18: Pour the Mold
When filled, insert the LED module (being help up by a clamp or tape or anything); make sure everything is straight before you leave it to harden!
NOTE: This stuff smells pretty bad, so work in a well ventelated area (such as a fume hood)
Step 19: Extract the Cast
Step 20: Polishing
Various stages in polishing/sanding. I couldn't get out all of the imperfections...
Step 21: House all of the components
Step 22: Insert the LED
Step 23: You're done!
I would take different birghness pictures, but it doesn't show up that differently on my camera (some sort of auto-brightness changer?)
Have fun with one of the largest DIY LEDs!