Kinda-Peasy DIY interior lights

[Lemosteam]

I bought some of that really thin PCB that @peteski recommended on another thread, along with some really nice LED's and some tiny slide switches in the hopes that I could make some interior lighting for my fleet of PRR P70's.

Now these cars have easily removed roofs so I decided to put the battery and switch inside.

I sliced 3/16" strips off the 9"x12" PCB sheet and cut it in half for two 4.5" long strips.  I laid down some 3M double stick tape on my desk and separated the two strips about 1/16" apart.  The LED's I bought have square clear housings with little SMD legs that stand the lights off the PCB slightly.  I made 5 marks on the tape 1" apart and soldered the lights at each mark making sure the + sides were on the same PCB strip. 

Then I trimmed up the 3V CR-1025 battery housing and bent the tabs to allow me to solder the + terminal to the positive strip. 

Next I made a groove in the - strip and soldered the switch's SMD housing's isolated legs across the gap to lock the switch in place on the assembly with the switch's terminals facing out.  A small wire from the - battery terminal to the center switch terminal, and another to the - PCB and done!

Lights off:


Lights on:


3M double stick tape inside the roof, off:


Inside the roof, light on:


Roof, lights on installed on the car:


Yeah I know, I have to yank the roof to flip the switch, but this cost a whopping $2.50 to make, versus $9+ for easy peasy which I am not sure would fit in my custom roofs.  Just wish it were easier to add my own reed switch, but...

[peteski]

John, since I replied to your  other thread about this, I figured I would duplicate my reply here.

I bought some of that really thin PCB that @peteski recommended on another thread, along with some really nice LED's and some tiny slide switches in the hopes that I could make some interior lighting for my fleet of PRR P70's.

Now these cars have easily removed roofs so I decided to put the battery and switch inside.

Pretty clever John.
As an alternative you could just buy a 5V white (or warm white) self-adhesive LED strip and hook that up to your 3V battery.  The resistors are already installed and even at 3V, the LEDs should be plenty bright for realistic interior illumination.  And the strip is very thin and easy to stick to the roof.  Just cut it to length, and attach the switch and the battery.

Here is a sample eBay listing (there are dozens of different sellers selling these). Just make sure to get one using 3528 (some sellers call them 2538) SMD LEDs. Those are fairly small. You don't need any larger LEDs.

https://www.ebay.com/itm/Warm-White-LED-Strip-USB-Power-DC-5V-SMD3528-Home-Holiday-lights-Lamp-1-2-3-4-5M/132907900237

[Lemosteam]

By now you should know I like to build things, LOL.  I have asked the seller what the spacing between the LED"s is because it it not specified, nor is the color temp.  Sometimes you never know what you are going to get without the specs.

I also like the fact that the PCB is more rigid than those, bendable even.  I also wanted a fairly shallow profile, those strips are really thick, I've used them before and the adhesive sucks.  Remember those basement lights I made and used a huge rectifier to convert the 12v AC to DC?  I had to staple them to plywood because the tape would not stay.

[peteski]

By now you should know I like to build things, LOL.  I have asked the seller what the spacing between the LED"s is because it it not specified, nor is the color temp.  Sometimes you never know what you are going to get without the specs.

I also like the fact that the PCB is more rigid than those, bendable even.  I also wanted a fairly shallow profile, those strips are really thick, I've used them before and the adhesive sucks.  Remember those basement lights I made and used a huge rectifier to convert the 12v AC to DC?  I had to staple them to plywood because the tape would not stay.

I like to build things to John. But sometimes it makes sense to me to get something that is already assembled.  The strips (as you know) are flex PC-board, around 0.010" thick.  Going by the strip I bought (from a different seller a while ago, the LEDs themselves are also not very thick. Flex board with the LED is around 0.045" thick. LED spacing is likely standard for those strips, around 0.640". If the adhesive sucks, you can always glue them to the roof using another adhesive, or glue some styrene strips across the LED strip (sort of like if you were using staples).  Also, the pressure-sensitive adhesive is not really designed to work well on porous surfaces (like unfinished plywood).

The cool white is a bit bluish, while the warm white is usually similar to a color temperature of a halogen bulb (3000K).  But if you are worried and want some specific color temperature then you are right - you are better off buying discrete LEDs and building your own strip (with no resistors).   

I simply tried to present an easy alternative to what you have done. Some modelers might prefer such ready-to-use alternative.  If you wish I can delete my posts.

[Lemosteam]

No worries, I know you like to present other options and that's cool!  I think they might be a bit farther apart than 0.064", lol.  Adding more and more thickness is not where I want to head with these either.

If someone else wants to proceed that way they can.

[wm3798]

The P-70s have a black clerestory roof, no?  How hard would it be, and how obtrusive would it be, to cut a slot in the clerestory for the nub of the slide switch to be exterior enough to be able to flip the switch without having to disassemble each car?... as I recall you're building a lot of them...

I love the set up, and especially love the cost...I'm looking at lighting my burgeoning fleet of vintage cars... (that single flickering bulb in the middle of the old Rivarossi cars ain't floatin' my boat).  Not sure where I'll hide a slide switch on a fluted car, but the clerestory trick could be just the ticket on the heavy weights.  It'll be harder to disguise in the gray B&O roofs, but the black PRR one should be damn near invisible.

Lee

[Lemosteam]

@wm3798 See this one.  In this case I ran the wires outside the car and mounted the switch between the boxes and did not use the PCB because I had specific light placements in the interior.





In this case I ran the wires outside the car and mounted the switch between the boxes.

My custom Arch roofs would not have a place for that.  Also i was thinking of mounting the switch inside the glass at either end and one could mill the end door glass away to provide access to the switch, but I would definitely do it at the opposite end from the battery.

Here is the style of roof it's in:

[wm3798]

Ah yes, the full roof...  I should have paid attention to your build more closely.
Somewhere on the end would be more convenient, but you'd still have to uncouple/handle the cars to get to the switch.  What would it cost to add the magnetic reed switch?  If it still comes in less than the Rapido rig, it's probably worth it...

Lee

[Lemosteam]

A latching reed switch is required and they are expensive and may even require additional components (I asked Pete privately).  You'd be better off with the E-P lights at $9 apiece.

[peteski]

No worries, I know you like to present other options and that's cool!  I think they might be a bit farther apart than 0.064", lol.  Adding more and more thickness is not where I want to head with these either.

If someone else wants to proceed that way they can.

It is 0.640". Corrected. 
Just out of curiosity, how thick is your circuit, and which specific LEDs did you use? I'm also wondering why you didn't just use single full-width PC board and just cut the copper cladding in the middle?  Using the tiny LEDs to mechanically hold the 2 halves of the board together makes it quite fragile.

Since the question was asked, here is a thread about latching reed switches: https://www.therailwire.net/forum/index.php?topic=43577.0
And a thread about lighting a car using those eBay LED strips (but in that example 12V, with a de-flicker circuit): https://www.therailwire.net/forum/index.php?topic=29654.0 .

Another question I have is about the color of your LEDs:  are they white, or yellow/amber?

[Lemosteam]

@peteski , here are the LED (yellow) https://www.goldmine-elec-products.com/prodinfo.asp?number=G21688

Here are the switches: https://www.goldmine-elec-products.com/prodinfo.asp?number=G23077

And here is the 0.010" thick PCB: https://www.goldmine-elec-products.com/prodinfo.asp?number=G18750

I am going to flip the battery to its other side to move it up into the roof so it is less visible and since I will have to remove the lights for battery replacement anyway.  The 0.64 is way too close for me; I have mine at 1" spacing which I think is perfect.

[peteski]

@peteski , here are the LED (yellow)

Here are the switches: https://www.goldmine-elec-products.com/prodinfo.asp?number=G23077

And here is the 0.010" thick PCB: https://www.goldmine-elec-products.com/prodinfo.asp?number=G18750

Thanks John!

[wvgca]

looks good, perfectly fine

[Lemosteam]

Made a set of lights for my PBM70 lit the cabin and the mail room.  The baggage windows stay surprisingly nice and dark between the cabin and mail room.

Battery inset week.


Mounted the switch inside.


End view of roof with end door opening for the switch.


Lit up!

[peteski]

I like the way you hid the switch, with the entire roof assembly (and the lighting circuit) as a single removable unit. Clever!