LED Lighting Basics For Shadowboxes and Buildings

5050 LED dimensions are 5.0mm x 5.0mm!  50mm x 50mm would be a ginormous LED!

The 10 and 14V outputs on a Z-4000 are AC (not DC).  If you intent is to use these specific LEDs with typical O-gauge transformers (which also put out AC voltage), you'll need some intermediate circuitry that can be discussed if need be.

Because of the low-current requirements of LEDs, pretty much any wire-gauge you can find will work.  Hard to say what's best since it's a combination of factors - ease-of-handling, routing around the structure, susceptibility to breakage, plug-and-playability, etc.  The point being it is unlikely you'll be constrained by the electrical properties of the wire.

Stan2004-

Thank you for the corrections!

We are now looking at strip LEDs. The strip LED should give a more even distribution of interior ligh. Does anyone have experience with this product for lighting buildings or shadowboxes? My initial concern is the resultant brightness my be too much. If that has proven the case for you, what have you done to reduce the brightness? 

Strip lights are great. The best way to dim LEDs is with a PWM dimmer purpose-designed for LEDs. You can get residential-style ones from SuperBrightLEDs. Bare boards controlled by pots cost almost nothing on eBay. If you go with color LED strips, there are inexpensive controllers that let you control both color and brightness using IR remotes.

And yet another option from Stan2004, is to install longer wires in-between leds like this.  Works well for marker lights on observation cars, could work for lights extended along a building wall.

ToddModel posted:

We are now looking at strip LEDs. The strip LED should give a more even distribution of interior ligh. Does anyone have experience with this product for lighting buildings or shadowboxes? My initial concern is the resultant brightness my be too much. If that has proven the case for you, what have you done to reduce the brightness? 

If too much brightness is the issue, I was curious about your choice of the Little Dot LED.  They claim 30 Lumens of output.  I don't know how you design your products wrt illumination, but 30 Lumens is a generous dollop of brightness for a point-source in 1/48 scale.

I'm not familiar with your product line and don't know your target or typical customer but based on what I've seen/read on OGR, the bias is toward plug-and-play, no-soldering, no-math, ease-of-use, etc..  IF I am reading the tea-leaves correctly, you cannot ask your customers to fire up the soldering iron.

Note that those LED strips come in both 12V and 5V versions.  Most discussion on OGR has been on the 12V version because that's what is more commonly available and that level of voltage is generally available in O-gauge whether as track-voltage for rolling-stock passenger cars or as Accessory voltage for layout lighting.   I don't have the WS lighting system but it may be that the lower-voltage 5V LED strips may be compatible with your existing controllers.

Separately, as for your initial inquiry about wiring, perhaps you've already looked into doll-house lighting.  They use so-called tape wire and there's a whole set of connection and inter-connection schemes for illumination.  I believe Cir-Kit is the proverbial 800-pound gorilla in that market.

As TedW points out, yet another idea wrt the LED strips is to study how they are configured, and cut them to create economical low-profile LED point-sources.  When purchased on a strip, LEDs are typically only a penny or two.  Yes, you have to then attach wires but having the tape as a "substrate" or backing simplifies soldering wires to those miniscule surface-mount LEDs.

I’ve added LED strip lights to Todd Model shadow boxes with results that I find very pleasing. Most of my buildings also include interiors and figures as shown in this shot. I used construction paper as shades on some windows to reduce or block some light. I also have a simple and inexpensive dimmer connected to the circuit to reduce illumination as desired. 

The lights are short segments from 3 meter (16.4 ft) rolls of 12 volt LEDs, which are available from eBay or from Amazon ($7.98 for 300 lights). You can cut segments from the roll in groups of 3 to achieve just about any length needed. For these shadow boxes I used 2 x 3 LED segments for a total of 6 LEDs per floor, which is more than adequate. Probably could use only one 3 LED segment and still have plenty of illumination. 

Normally, I solder a red and black wire to the ends of the short strip. I drill a small hole in the copper connectors, tin the ends of the wire, insert thru the holes and hit with my small solder iron for a few seconds. I use 22 gauge stranded wire, which can be cut to any length. I also have used 28 gauge red/black paired wire for LEDs headlights in vehicles, which works fine, confirming what others have posted here. 

For those intimidated by soldering, there is an easy alternative as shown. On the left is a soldered example. On the right, a plastic clip that is made specifically for these strips (Amazon - 10 for $5.85). Normally, these come with a short length of red and black 22 gauge wire (6 inches), but it can be extended with simple crimp on butt connectors. I used small diameter connectors, and run the wires through 1/4 inch square plastic channels that fit exactly in the space provided in the shadow boxes and run between the floors. I connect these to a wire block with a 12 volt (DC) feed controlled by a dimmer. 

Here’s a shot of a dimmer. I actually used 3 of these with separate circuits to allow for different light intensities. But based on my experience, this is probably overkill - one dimmer for all lights would work fine for most. 

These are readily available from Amazon ($5.86) or from eBay (sourced from China, these are even cheaper, but takes 3 weeks to arrive). 

BTW Doug - when are you going to offer more of these shadow box buildings for Main Street? I love these, but I have room for at least another 3 or 4 feet more. Even variations of the originals would be great!