DIY Lighting Up Modulars.

[jus1973]

Owing to the costs of lighting kits, some being almost 40-50% of the price of a modular building, I’ve realised that if I want to light up my modular town, I’m going to have to go down the DIY route.  Having searched here, and on the web in general, I’ve found lots of conflicting advise and methods, so am going to try to make the best of it I can with my very limited knowledge of wiring.

The plan is for each modular building set to have a parallel circuit of either 3 or 5 mm LEDs for interior ceiling based lighting.  A few might venture to the outside, like Downtown Diner, to light the sign.  Each LED will have its own resistor, to step the voltage from a USB power bank, (5V) to the 3.2-3.4V range required.  I’m going to mount the LEDs in the modified plates with holes This will keep the costs down to perhaps no more than £2 per building, once I’ve got wire etc purchased.

Before I start, is there anyone out there with experience of doing it this way, or a simpler way, with knowledge they’re willing to share?  

As I have successes, and the inevitable failures, I’ll try to post here too, once I coerce my flickr account to actually work for pictures.

[Berthil]

The lighting kits are indeed too expensive for what they are, have visible witring and use mostly batteries for power. All not an option for my 40 modulars.

So I did two modulars with cheap LEDs and thin wires with the aim to blend in the LEDs, have no visible wires and still be able to take the levels apart without a hassle. I would like to do all my 40 modulars but have no time for it. May be when I'm a pensioner and get to be 90 years without going blind and with steady hands :)

Where there were no light fixtures I created them with LEGO (like above the bar and table in the Diner). The 0,2mm wires fit between tiles under the tiles. There are thinner wires to fit even between bricks but these wires will break very easily. I used rigid hoses to hide wires where needed and used thick copper wire as attachment points between levels. May be copper nails with large heads would work better there, if I do more modulars I would use these. Other than that I'm very happy with how they turned out. Little modification of bricks so the whole thing is reversible into standard modulars.

For the lights outside I bought enough old type of lanterns as they are thicker. I drilled a hole in the center for the wiring with a drill standard. The newer type of lanterns are to thin for a hole for the wire.

I've used one resistor for the whole house with all leds hooked up in parallel. I calculated the resistor to use the LEGO 12V train power supply and wires to keep it all LEGO. This also has the nice side effect that all LEDs are dimmable with the train power supply. Since LEDs are not power hungry, one train power supply suffices for the two modulars and I expect I can attach more. Using batteries was not an option for me.

Not sure what I would do if I do more modulars. With only a ceiling light in every room or again use existing light fixtures or add light fixtures to blend in the LEDs. A few LEDs on the sealing would be enough for the nice effect of a street of lighted modulars in a dark room but there would be no outside lighting. May be a kind of modular system with a few LEDs on the back of a wired LEGO plate with a plug to stick under the floor of every level would be a quick way to light up modulars without too much hassle. 

Here's a video and Flickr album of the two modulars.

 

Flickr Album:

 

Edited July 24, 2022 by Berthil

[jus1973]

Thanks for sharing Berthil.  Some good options there for the outside lamps, that I haven’t yet thought about doing.  

Interesting that you have one resistor for the entire circuit, rather than 1 per LED, as my plan originally had it.  I might experiment.

40 Modulars!  Wow.  I’ve got 10 of the original Lego ones, plus GBHQ and the Spring Lantern Festival set to do, plus I’m just designing and building my own little town train station.  I thought I had a job ahead of me. 

[jus1973]

So,  Just a little update to this topic.  I’ve managed to have a first bash at this, and have placed 6 white 3.2-3.4V 5mm LEDs in a MOC train station build.  These are powered from a USB power bank.  I had to use 3 resistors in parallel to get the correct voltage and current.  It’s all a bit rough atm, as my soldering skills leave a lot to be desired.  

The LEDs are bare atm, but will look at beautifying them at some point.  I’ll post pictures when i tidy it up a bit, and made the second circuit with yellow LEDs in the station masters house that forms the remainder of the build.  These need a different voltage, so can’t form 1 circuit for both parts.

[westphald]

On 7/24/2022 at 10:19 AM, Berthil said:

The 0,2mm wires fit between tiles under the tiles. There are thinner wires to fit even between bricks but these wires will break very easily.

What 0.2mm wiring are you using? Solid, stranded, what is the guage and jacket? I'm looking to add lighting to a MOC and see that some of the kits use "aviation-grade extremely thin wire" that appears to be thinner than any jacketed 34awg or 36awg I've found.

What are the even thinner options you're aware of?

[AllanSmith]

I  would go with an Arduino Nano and NeoPixel LEDs. Only one resistor needed for all the daisy changed LED's. The Arduino can be programed to turn on and off individual LED's, adjust the colour and brightness.

Edited September 15, 2022 by AllanSmith
Grammar

[CDM]

Looking forward to seeing what you're doing. I've been kicking this around for my winter village.

[jus1973]

11 hours ago, AllanSmith said:

I  would go with an Arduino Nano and NeoPixel LEDs. Only one resistor needed for all the daisy changed LED's. The Arduino can be programed to turn on and off individual LED's, adjust the colour and brightness.

I’m looking at doing this with a Pi, for traffic lights etc.  As for the LEDs, I’m quite restricted by finances so I’ve just gone for some fairly cheap 3mm and 5mm versions for the time being.  I’ve had to parallel resistors to get the required current and voltage., but I’ve had to use parallel circuit for each LED, as current drop is too much running from a 5V USB source.

[Toastie]

4 hours ago, jus1973 said:

I’ve had to parallel resistors to get the required current and voltage., but I’ve had to use parallel circuit for each LED, as current drop is too much running from a 5V USB source.

Seems to e quite some work on each LED - but it works, as you said! And this is the most important thing.

I am a bit puzzled about the parallel resistors bit - these are in series with the LED as current limiters, right? So one resistor for one LED, correct?

Spoiler

 

BTW, I had some nice surprises with these RGB LED stripe controllers. They are running on a nominal voltage of 12 V - but you can "dim" them down; 9V of an RCX is fine, even dimming further using the RCX outputs works fine. Just make sure that you get RGB LED color stripes that can be cut to rather small "units" (of about 10 cm length). Needs some soldering here and there, but I believe it is the cheapest way to get any thinkable light color for illumination. Also, you can have the controller executing some "program" like flashing, changing colors, fast, slow, etc. The controller does not forget the last setting when powered down. And for short strip sections, your tiny cables are just right.

I am using these for a lighthouse, just faking the rotating mirror by having the light slowly brightening up and down, for a scary ;) tunnel entrance with some slowly changing light from green to red, and for some underwater "diorama" with a ship wreck down there and rather quickly changing colors, as if the sun would shine through the water. As said, these are amazing - and comparably cheap. I got them for less than €5 (actually 1.90€) which includes the controller and the little remote.

 

 

Sounds like a lot of fun, what you are doing!

All the best,
Thorsten

[jus1973]

20 hours ago, Toastie said:

Seems to e quite some work on each LED - but it works, as you said! And this is the most important thing.

I am a bit puzzled about the parallel resistors bit - these are in series with the LED as current limiters, right? So one resistor for one LED, correct?

  Hide contents

 

BTW, I had some nice surprises with these RGB LED stripe controllers. They are running on a nominal voltage of 12 V - but you can "dim" them down; 9V of an RCX is fine, even dimming further using the RCX outputs works fine. Just make sure that you get RGB LED color stripes that can be cut to rather small "units" (of about 10 cm length). Needs some soldering here and there, but I believe it is the cheapest way to get any thinkable light color for illumination. Also, you can have the controller executing some "program" like flashing, changing colors, fast, slow, etc. The controller does not forget the last setting when powered down. And for short strip sections, your tiny cables are just right.

I am using these for a lighthouse, just faking the rotating mirror by having the light slowly brightening up and down, for a scary ;) tunnel entrance with some slowly changing light from green to red, and for some underwater "diorama" with a ship wreck down there and rather quickly changing colors, as if the sun would shine through the water. As said, these are amazing - and comparably cheap. I got them for less than €5 (actually 1.90€) which includes the controller and the little remote.

 

 

Sounds like a lot of fun, what you are doing!

All the best,
Thorsten

WRT to the parallel resistors, then I don’t think I explained it well.  To be honest, I’m just learning this myself, through various websites and a bit of trial and error.  Certainly had a couple of failures, but luckily nothing causing any damage.

If you have a given number of LEDs in a standard parallel circuit, and their individual voltage drop is 3.2V, at 20mA, for example, then you need to place a resistor of a reasonably specific value at the on the lead stemming from the positive power terminal, before the circuit splits.  Quite often, this value is not a standard resistor value, so you use a combination of resistors in parallel with each other, to reach this required value.  

So far, I’ve got two circuits made this way, driven off 5V USB powerbanks. I aim to make a few more now I have some parts in which to hold the LEDs in.

[Monger]

On 9/13/2022 at 9:35 PM, westphald said:

What 0.2mm wiring are you using? Solid, stranded, what is the guage and jacket? I'm looking to add lighting to a MOC and see that some of the kits use "aviation-grade extremely thin wire" that appears to be thinner than any jacketed 34awg or 36awg I've found.

What are the even thinner options you're aware of?

.1mm magnet wire?

The insulation comes off with heat from your soldering iron making it easy to work with. 

[westphald]

I know that magnet wire is an option, a decent one for building MOC's, but not great for technic creations that may have pivot points. I'd like to find the thinnest stranded, jacketed wire.

It seems that most of the lighting kit manufacturers use very thin jacket 32awg or 36awg wire. Stranded or solid, I haven't figured out yet. I've located some surprisingly thin wire, but nothing down to 0.2mm with a jacket.

I'm also trying to figure out what connectors they are using that are small enough to fit through a technic pin.

[Berthil]

I've used this 0,04 wire.
https://www.conrad.nl/nl/p/210-10-draad-2-x-0-04-mm-rood-zwart-10-m-1437320.html
One color of this wire fits under the groove of tiles. 

I know some use 0,01mm wire without jacket in ships. It fits between bricks but it breaks very easily and not advised to use.
If you have on old small (broken) electro motor it is possible to use the wire of the coil.

[jus1973]

Wire availability is an issue, and I’ve made do with scraps I found at work, which are a bit too big to be honest.  I have had to replace a 1 stud brick with two one stud plates, leaving a plates depth to pass the wire through.  whilst the wires are not that thick, they’re just a little too thick to pass either side of the bottom of a round 1x1 plate.