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Customer Testimonials » The LED Build

January 11, 2010
by Farmer
Farmer's Avatar

In the following thread I will share my ideas and progress for the LED build. Please feel free to comment or offer suggestions.

I decided to use some scrap dry-erase board for my LED mount panel. I measured out a 5/8 grid, slightly smaller than idea presented in the manual. Not wanting any wires on the front of the panel I drilled 2 small holes 1/8" apart for the led leads. I opted to drill a stack of three at once for a possible future expansion. Drilling the panel

240 Holes Later.... 240 Holes Later

I noticed they used some wax paper to both hide the wires on the front and diffuse the light coming from the LED. I will not have wires to hide, but I don't want the LED's to be blinding to the eye either so I using some 220 grit sand paper to "frost" the LED's, a very time consuming process. I read someplace that the window frosting aerosol spray works just as well for this purpose. In the images below you can see the difference this makes. Frosted Not Frosted

One by one they get sanded and glued directly to the board.

More to come next month when I am done sanding all these LED's.... (LOL)

January 11, 2010
by Rick_S
Rick_S's Avatar

Great write up, I'll be looking forward to the future installments. The sanded look is nice on the LED's, though I'd imagine it does take a lot of time. :D

Rick

January 11, 2010
by ecornwell
ecornwell's Avatar

I look forward to seeing how you wire the led's up. I just finished my array this weekend and did it on foam board like the examples. I also purchased a thin piece of Plexiglas to sand to get the same effect.

Great work!

Eric

January 13, 2010
by Farmer
Farmer's Avatar

Proof of concept, and other side notes.....

Finally got all the LED's sanded. I was using Elmer’s glue to fasten the LED's to the panel, but I found it does not stick so well to the LED itself. They quite easily break loose. Regular super glue does not work well either. It has a tendency to want to run down and coat the LED lead. (Probably not good if you want to solder it) I was also using the liquid type super glue and not the gel type. I picked up a tube of Loctite 6min epoxy and this seems to work VERY well. Before diving into the actual build I put the following mock together to make sure my design intent worked. I glued/epoxied 4 LED's to one of my boards and proceeded to wire them up as shown below. I would not recommend this approach if you are easily frustrated with tedious work. :-)

Iso

Side

I put a power source across the different leads and got all the LED's to light up. Perfect my solder joints a little and I think I am good to go, though I am a little concerned with shorts in this method of assembly. I think bending the leads over and putting the wires flat on the panel, as opposed to the loop method shown, may be a better approach.

Below is an Autodesk Inventor model I made while brain storming. It shows the wiring a little better. Can anyone tell me if I am headed towards disaster with the daisy chain method of wiring? The Green and Blue wires are not quite what is shown in the NK manual.

Auto Nerd

January 14, 2010
by Rick_S
Rick_S's Avatar

That looks as though it would work. You are essentially hooking it up the same way. I'm assuming that your green/blue combo becomes your column wire and each yellow is a row base on your illustration. Soldering the LED's like this is very tedious as I'm sure you've discovered by just your few. I know exactly as I've been there. If you haven't seen my build posts, read newsletter #8 and it give the forum links. I used Christmas LED's and the soldering was the most time consuming portion of the build. The end result is worth it though. They also have some links to additional functions I added to the array to give it a few more effects.

Looks good so far!!

Rick

January 17, 2010
by Farmer
Farmer's Avatar

Better Build...... No Wire Needed

I expanded on the idea of folding the LED leads over. I Like It... Looks like I can get the panel depth down to an inch or less excluding the LED bulb. Soldering becomes a bit more joyful also.

The upper row wires/rails? become quite ridged after soldering them. I plan on running the colums parallel and connecting them at the bottom/top?.

Lattice

Lattice

Let these horrible solder connects stand as proof for need of past/flux for making 'good' connections... LOL

BTW Rick_S.....

I did see your box before. Right after I discovered NerdKits I Googled it/them to learn more. Your build was one of the first items I found, thanks for posting that great build... :-) I gathered a few good ideas reading your thread(s).

January 19, 2010
by Farmer
Farmer's Avatar

Final Assembly and Testing......

We used old Lego bricks and some thick double sided tape to mount the breadboard. I plan on hard wiring the components and enclosing the panel so this is only a temporary solution.

Stands

Measure and cut wire.

Wire

Neatly tucked wire under row rails.

Wire

Wire

Wire

Q & A.... The power supply that came with the Nerd Kit is labeled as: 9v 300mA. My volt meter says it is 14v. ??

Wire

Will it work on the first attempt? I posted a short vid of the acid test: nerdkits LED Test

Now... to dive into the code and personalize it a bit.

January 20, 2010
by Rick_S
Rick_S's Avatar

Great job!! I love the wiring on the back looks very neat and tidy. Much better than the squirrels nest my Christmas lights made. As for the power adapter, it'll be fine. the voltage rating on many wall-wart type adapters is based under an assumed load. With no load the voltage is typically much higher. That is why they must be run through the regulator.

Congratulations on a job VERY well done!!

Rick

January 20, 2010
by Farmer
Farmer's Avatar

Thanks for the response.

In all this was a great experience. If I were to do it again the only changes I would make are:

1) Change the LED center to center spacing to 11/16. The 5/8 spacing worked, but a few of the leads did not quite reach the next for the upper rails. I had to bridge a small gap with the solder on a couple of connections.

2) Spray frosting for the LED bulbs. I probably had at least 6-8 hours of sanding LED bulbs.

3) Glue... Elmer’s stuck to the board, but not the bulb. Super Glue (liquid) did not really stick to anything but the LED leads. The fiber board base also soaked it up like a sponge, leaving very little glue left for actual part contact. The 6min epoxy gel worked well, but required many small batch mixes. Also if you should attempt the epoxy method I found it best to apply with a toothpick. Just put a dab on the bottom of the LED. As you go the epoxy starts to harden, at this point it is easier to wrap the taffy like substance around the leads themselves and squeeze it out as you push the leads thru the board.

This should be a lot of fun at the next family-get-together.

Thanks again to the Nerd Kit Team, you truly have a exceptional product.

Best Regards - Federal Farmer

January 20, 2010
by Phrank916
Phrank916's Avatar

Federal Farmer-

I like the way you only had to use the LED leads to conenct them all together. My only question is: how easy is it to get a short across a row / column? Is it just the way you've bent the leads that creates enough "airspace" between them so as to prevent shorts? I might use this convention when I get around to building the array.

Ted

January 20, 2010
by Phrank916
Phrank916's Avatar

Sorry, had one other question: Just for clarification, did you mean to say 9/16 as the spacing for the next attempt? If you can't already tell, I like your soldered grid method and I'm thinking of using it on my array, so I just wanted to be certain. :)

January 20, 2010
by Farmer
Farmer's Avatar

Yes, it is just the "airspace" that makes it work, and yes I meant 9/16 (grin, oops). After soldering the upper rails together they become much stiffer than just a single lead sticking up. In hindsight if I were to do it again I think I would use something very thin as an insulator (cardboard?) and bend the row leads flat to the panel also. That said you could probably increase the LED spacing to about 3/4 (20mm). Then use a thin piece of plexiglas and mount the components directly to the board itself and you could probably get the entire assembly under 3/4 (20mm) depth, and that includes the height of the LED bulb itself.

Count out the LED’s, my kit had a number of “extra” LED pieces I could have experimented with. Also your panel thickness will vary the maximum LED spacing.

A few more pics for the interested.

Plexiglass

Plexiglass

Plexiglass

Plexiglass

Plexiglass

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