The project that I have been working on lately revolves around trying to get somewhat typical lighting into my buildings and structures. I've always been interested in this part of the hobby/layout building, and some recent successes with LED lights, which are great given their relatively long life span and low heat output, have made some of my desires- to add more 'realistic' types of lighting effects to buildings -very achievable and very affordable. It also hasn't hurt to give me an opportunity to work on my soldering skills!
I first started using 'pre-assembled' LED lights, particularly the 'universal' kind, in some buildings, which I was purchasing online from ModelTrainSoftware.com. While these work quite well, at around $5 a pop, I figured it would be far more cost effective if I figured out how to do it myself.
There are really only two things to do after I decided to start trying to 'build' my own LED lights. The first is that I am going to have to learn to solder. The second, is to figure out all of those voltage, ma, and resistor calculations. There is no short cut for the former, however, for the later, I've found the LED Center and their "linear1" website which features a foolproof (nearly) calculator for both single LED's and the LED's in series.
From there, its all about figuring out your voltage source, and then getting the right LED's and the right resistors. I've started to get these from eBay given the amazingly cheap prices you pay for quantities of 50 or 100!
The lighting projects I am most interested in are adding some 'back lit' signs to buildings and signs as they seem to be nearly everywhere. Its an area of lighting that I expect to give a lot of 'color' and 'life' to my layout. Other than neon signs, these seem to be the most common method for stores and other commercial entities. You can kind of see the effect I am going for in the above picture, which has a typical 'unlit' sign between two 'backlit' signs (which is clear plastic added in after cutting out the original plastic in those parts of the building).
Its a bit hard to tell from the photos (I could not get the right shutter speed to show it accurately) but what I've done is collected various types of clear, flat or cube-shaped plastic, reduced it to the appropriate size for the sign (which means lots of hand sanding, difficult cutting, or grinding on my belt sander), drilled a small hole for the LED to be glued into on the 'back' side, and applied a white decal to the sign front (I am using the Testors Inkjet, white backed decals, which have not been altogether succesful).
You can see one building face in progress, with all of the LED's, wires, and resistors sticking out.Wallah! Backlit signage! However, I have mixed feelings about the progress so far. The LED's certainly provide enough luminosity to appear like 'backlit signs',but the decals are a weak link, which is not too surprising. I have tried 'transparent' inkjet stickers (the kind you can get at the office supply stores), but my results with those were awful; they just don't 'absorb' enough ink. On the other hand, while the decals absorb enough ink (in fact, I cannot use 'photo-quality' settings with my printer as that puts too much ink on the decal and it melts away in the water, even after sealing with dullcote or the Testors decal bonder sprays) but lose a lot of crispness in the process. I may double up some decals in order to add some 'crispness' and color.
One final comment on LED's is that they have a very 'focused', almost spotlight-like beam. This is great for headlights, but not great for signage. I'm trying a lot of different things to overcome this affect, from sanding the LED to sanding the clear plastic the LED will be mounted in (to diffuse the light beam a bit), but one of the better looking signs is the backlit "Burger Konig" sign in which I did not embed the LED's in the plastic, but rather attached them further behind the sign with a glue gun (glue guns, of course, emitting that clear gooey mess, which works pretty well for 'diffusing' light). This distance back from the sign allows for the narrow light 'funnel' from the LED's (of which I used 3 in this case) to 'spread' rather than maintain a tight circle.
I'll add additional updates and photos on this project, hopefully I will get a 'city block' done soon and can move onto other parts of the layout!
Looking good!
ReplyDeleteLearning to solder is not so bad. Indeed, soldering is a skill that opens lots of doors in this hobby! For one thing, the price of an LED drops from $5 to 5¢ :D
Get yourself the 30W fire-starter from RadioShack: It's only $10, and it's good to learn on. Get a nice stand, the kind that uses a giant spring to hold the iron. You also want flux-core solder, perhaps a solder wick. From non-RadioShack sources, get yourself a third-hand—a good one can be had for as little as $5 at a fly-fishing shop. RadioShack's third-hand tool is not very good. Also, you will find that heat-shrink tubing in various diameters is a must—it beats the hell out of using electrician's tape, and keeps your projects from shorting out.
Finally, you only need to know a few things to calculate resistors for LED. The first is Ohm's Law:
V=IR
equivalently
R=I/V
R=resistance, V=voltage, I=current.
The second is when you have multiple elements (resistors and LEDs; multiple LEDs, etc) in a circuit, how to get the numbers to do the above calculation:
http://www.allaboutcircuits.com/vol_1/chpt_5/1.html
Finally, just know that LED's have almost no resistance; use 0 in your calculations.