Inspection Pit Lighting

[michaelp]

I know that there is a lighting kit available for the 'Scalescenes' inspection pit but does anyone know of a lighting kit for the 'Peco' inspection pit or which bulbs or LEDs would be suitable?

Thanks in advance.

 

Michael

[14Steve14]

Not having seen a completed peco inspection pit i dont know if they already have pre drilled holes for the lights. if they do not various LED lighting strips could be fitted and connected to a 12v supply. Most of these strips could be stuck in place as required.

[michaelp]

Thanks for the reply,

 

I've been searching for more info or photos of lights installed in the Peco inspection pit but haven't come across anything yet.

Thanks again.

 

Michael

[gwrman]

Hi when I fitted lights in my pits I used 5mm x 2mm Ultra bright rectangular LED's http://www.component-shop.co.uk/html/rl60.html

to stop light bleed I painted the sides with white enamel and when dry I put a thin strip of white insulating over the paint as well, the fitted into holes in the sides of the pits. Unfortunatly I don't have any pictures, as I've gone O gauge.

[lyneux]

Other people have used these to emulate fluorsescent strip lights in 4mm:

 

http://www.maplin.co.uk/side-looking-leds-10382

[vac_basher]

Other people have used these to emulate fluorsescent strip lights in 4mm:

 

http://www.maplin.co...king-leds-10382

 

I know this is an old topic, but it's something I'm looking into at the moment for a project I have on the go. I was looking at strip LEDs but I wasn't too keen on them, a bank of three LEDs scale up to 12 foot legnth by 18 inches width, which seems a bit too big for OO gauge.

But these are very interesting, Lyneux.... I'd love to see some photos of these lights in operation, if anybody has them.

I can't quite make out the size on their website though, is it 9mm legnth?

Also, is the wiring complicated for these?

[Xerces Fobe2]

I fitted small yellow LED's into the pits with the wires going through the drain covers in the bottom.

 

 

XF

[lyneux]

But these are very interesting, Lyneux.... I'd love to see some photos of these lights in operation, if anybody has them.

 

Jonathan Baulch's Laira utilises these for the inspection pits to good effect. Are you a member of DEMU? If so, you can see more of this layout including the side facing LEDs on the DEMU forum.

 

I think he got the idea from Andi Dell. Not sure if/where Andi's used them. Maybe he'll pop up to tell us?

[Xerces Fobe2]

My pit lights were a bit of fun and are a little crude however given that they are under cover of the shed building and have trains over then a lot of the time however they always attract a lot of interest at exhibitions.

 

XF

[vac_basher]

Thanks Lyneux. Unfortunatly I'm not a member of DEMU

 

Xerces Forbe, I'd already seen photos of your layout on here. The effect of your lights is very good. But for what I have in mind I need something a bit more prototypical as I intend to take photos of locomotives inside my shed, so I'd really need alternating (left/right) "tube" type lighting on the pit walls.

 

If the Maplin ones are 9mm in legnth that scales up to just 2 feet, so a little on the short side. But now I'm wondering how two (or maybe even three) side by side would look....

[jdp298]

It'll take a bit of preparation, but an LED behind a frosted cover would also do the trick. There's a shop on ebay (brakepads88) sells suface-mount LEDs with wires already soldered on, I've used these in all sorts of station buildings as they can hide anywhere. I've generally found matt varnish quite good on clear perspex, but it might need a few layers to get a realy diffuse look. You'd also need to stop the LED 'burning through' the thickness of the plastic and giving it a halo effect; cardboard and tissue paper there.

[vac_basher]

JDP298 coincidently, just this evening I was experimenting a bit. In theory what I had in mind seemed like a good idea, but I thought the results were dissapointing....

 

(Appologies in advance for the poor photos)

Having obtained a sample of a SMD type LED strip I measured it up and like the ones I'd seen online this one was also 5cm long by 8mm wide. Far too big for inspection pit lights. So I thought I'd see if I could do anything with it to make it suitable for wall mounted tube lights....

 

With 0.5mm x 0.75mm plastic strips on a bit of 1.5mm plasticard (which represents the wall) i built a frame 3.7cm long by 3mm wide (the reson for these dimenions are that's the snuggliest the actual LEDs would fit in the frame - the stip goes behind the wall). I drilled 3 small holes through the "wall". And I then covered the frame with a bit of clear plasticard which I'd rubbed with sandpaper to make it opaque, although it wasn't opaque enough so I smeared glue over it (which made it more yellow/warm)

 

Then the strip of LEDs was stuck behind the wall, as can be seen from this photo.

 

Then I powered it up with a 9v battery and the results can be seen.

So that's not really satisfactory It's not really all that bad I suppose, if you're after a modern look, but the results are not what I'd expected.

I might go with this for my celing lights though. I'll see how they look once the celing's built....

 

But for my pit lights, I think I'm going to try the Maplin ones that Lyneuk has suggested above.

Although I'm confused, does anybody know if I'll need resistors with these? I hear some people saying LEDs don't need resistors because they can't burn out, but that sounds like nonsense.

I plan to wire them up in rows of either 12 or 24, so would each unit need a resitor or would one be enough for all? Something to keep in mind is that I want them as dim as possible because if I'd be photographing with 2 or 3 second exposures too strong lights would cause the photos to over-exposure - for my photographic style (with the smoke) I really need long exposures.....

 

Not easy to find something is it!

[lyneux]

Hi VacBasher!

 

All LEDs require you to wire a resistor in series with them to limit the current (not the voltage!). There are however, some kinds of LED that come pre-wired with a resistor as part of the package but these are rare and will it should be explicit in the advertising.

 

I've had another look at the Maplin link I posted for the side-facing LEDs and they definitely will require a resistor. Which resistor to use depends on how you will be powering them (with what voltage). If you go to this website (http://led.linear1.org/1led.wiz) and type in the following values: sourceV=12, forwardV=4, forwardCurrent=20 (from the spec on the Maplin site) it recommends a 470 ohm 1/2 watt resistor. If buying from Maplins I'd go for the nearest value resistor that is easy to get hold of that is slightly greater than this value, e.g. 500 ohm.

 

Having said that, given that you want to have a lot of these in your inspection pit, it might be better to wire them in series or parallel (make sure they are all the same way round!) and add a single resistor for the whole lot. The same website has a calculator for this: http://led.linear1.org/led.wiz

 

The Maplin LEDs are rather expensive at £1 a pop. It might be worth looking elsewhere for the same type of component and bulk-buying (e.g. Farnell, RS etc).

 

Cheers,

 

Guy

[lyneux]

Seems like express models do them for £0.65: http://www.expressmodels.co.uk/acatalog/WHITE_LEDs.html

[vac_basher]

Thanks Guy. That's a good explanation. I'll look into the resistors later when I'll be able to concentrate better.

Just one further question, what do you mean by wiring them in series or parallel?

 

The Maplin LEDs are rather expensive at £1 a pop. It might be worth looking elsewhere for the same type of component and bulk-buying (e.g. Farnell, RS etc)

Maplin do bulk prices too. For a quantity greater than 25 the cost goes down to 46p + VAT

[jdp298]

About LEDs. Searching Mr Google about explaining series and parallel will explain with pictures, but for now:

 

1. Series. The electricity flows through 1 LED, then the next, then the next, etc... Each LED has an optimum operating voltage, so with a single LED operating at, say, 3v, you'd need at least a 9v supply to run 3 in series.

 

2. Parallel. Each LED is connected to the power supply so that if you take it away, the power supply will still push electrons through the other 2. In this case you only need at least a 3v supply.

 

In both cases the total power drawn is the same, but for the reduction in voltage in case (2), more current is required from the power supply as it is split 3 ways.

[Trofimow]

Express Models do a LED that emulates a fluorescent lamp - but it's not cheap...

 

http://www.expressmodels.co.uk/acatalog/FLUORESCENT_TYPE_LED_LAMPS.html

 

Alan

[Xerces Fobe2]

I must admit if and when I replace/upgrade my depot the pits will be lit in more professional and realistic manner. That said the original plan was not for total accuracy but a bit of a wow factor for some of the younger models and it has worked well at Shows.

 

XF

[ian]

A recent layout build for a client included an inspection pit with lights. Initially I was going to use the Peco pits but given the difficulty in fitting believable lighting in them I opted for the Scalescenes pit with the lighting kit from Black Cat. It all went together easily and you can judge the results for yourself.

 

 

 

The lights are DCC controlled too.

[lyneux]

It's worth noting that many modern inspection pits are wider than just the gap between the rails. Often the rails are supported across the pit on steel beams, e.g.

 

I'm planning to model the pit shown in the link above for my model of Whatley. The challenge will be to emulate the lighting on the steel beams!

[lyneux]

I've finally found the manufacturer and part number for these: Kingbright KA-9219

 

http://www.kingbrightusa.com/category.asp?catalog_name=LED&category_name=KCSide-Looker+LED&Page=1

 

They are 9.2mm by 1.9mm. Interestingly Kingbright also do an 11.0mm x 1.4mm LED. This might actually be a better representation of a long fluorescent tube in 00.

 

However, I still can't find any UK suppliers other than Maplin and Express Models.

[lyneux]

Another UK supplier:

 

http://uk.futureelectronics.com/en/technologies/semiconductors/optoelectronics/led-segment-displays/Pages/1174622-SSB-LX02YC.aspx?IM=0

 

If that's really £0.41 for a pack of 10 then this is a good deal!

[shortliner]

I don't know if it will work as you want, but a rectangular piece of perspex, with the LED fitted to the end, shining into the perspex may work - we used to use edge-lit perspex display boards in the Approach rooms in ATC towers (ah, the fun of writing backwards in chinagraph!). It may need the back rubbed on sandpaper or even a bit of ally foil on the back What you are doing is using the internal light-reflecting properties of the perspex strip. A diagram may help

 

[vac_basher]

JDP, thanks for explaining that. Infact, I didn't know it untill now, but whenever I can I prefer to wire things in Series. I don't know why, but to my mind it just seams more easy.

 

XercesFobe, yours certainly has the wow factor!

 

Ian, that's neat. But personally I really wanted to stay away from card. I've had experiances of card warping and even moulding.

I must say those Black Cat kits seem very expensive to me. If you were to buy the components individually - that is 4x SMD LED strips and a dimmer - you'd spend about half. Horses for courses innit

 

Lyneuk, I used to have a bit of an obsession with the Yeoman and ARC Class 59s about 20 years ago - just thought I'd mention that

 

Now, from the data sheet the Future Electronics ones seem to be identical to the Maplin ones 9mm x 2mm - but at a much more conveniant price: 13 times cheaper!

In real life tube lights come in all sorts of legnths. There's a table here: http://en.wikipedia....on_tube_ratings

For me the dimensions don't have to be spot on accurate, but the one's at Bath Road were almost certainly of the 5ft variaty (I was able to measure from photos using bits of the locomotives as reffrence) which is equivilant to 20mm in 1/76th scale.

Those 11mm x 1.4 Kingbright ones look interesting.... Two of those togther would have done the trick. Pity they only have 8 in stock according to the website. And I don't see any prices on there

So it looks like I'm going to go with the Future ones, even if two of these ones together are slightly under a scale 5ft.

If the price on their website is correct you've saved me allot of money Lyneuk!! I just wish I could see a photo of them in opperation so I could see what kind of light they radiate. Still, at that price there's no harm in trying them really. I'll report my findings here in due course.

 

Shortliner. I like your idea. But wouldn't the wires coming out of the LED be a bit messy? Unless one were to build a tiny enclouser around the LED and have the wires going through the wall....

[vac_basher]

Right, been talking to Future. They've confirmied that the price of 41p per single unit, not 10 as we were suspecting. Seemed a bit too good to be true really didn't it!

 

Lyneuk, I need your help again.... Using the calculator you showed me I've worked out that I need 1ohms resistors. Could you kindly show me which ones they are on the future website please.