Whilst we have always expected to illuminate our main club layout, Medborough, the idea for these particular lights really started after one of our group brought in some items retrieved from the skip at work. This was several metres of LED strip lighting and a selection of LED drivers to power them. As soon as we powered up one of the strips the possibility for layout lighting seemed obvious. Although we were lucky to acquire our LED strips and drivers for free, they are readily available on the internet and not expensive – see Lighting Information below.

At most model railway exhibitions you will see wooden gantries or pelmets holding up strip lights or spot lamps. The lamps themselves are heavy and the fact that mains voltage is employed calls for special precautions – most exhibition managers insist on PAT-tested equipment. With the LED strip solution there is virtually no weight and the strips themselves typically run at 12 volts DC.

Our group has three layouts designed for exhibition plus one member layout. They are all different lengths and widths. For Medborough we had a specific challenge; most of the scenery bolts onto the back of the layout and it varies in depth, so the layout width varies considerably. Our aim was one set of lights for all four layouts since, apart from our own open days, they would be unlikely to be all exhibiting at once.

The second breakthrough came when I purchased some studio lamp stands for a completely different purpose. I acquired two telescopic stands with fold-up legs on eBay for under £25 including postage; they have a maximum 2.23 metre height. These are Chinese imports and, whilst I’m not sure they would withstand the rigours of daily professional studio use, they would be ideal for holding up the very light structures we were considering. They also come with a convenient carry bag. The breakthrough concerned the cost as professional quality studio stands would be prohibitively expensive. We have used 6 stands to hold up 6.25 metres (20ft 5in) of lighting; this is 5 strips each being 1.25m (4ft 1in) long.

Whilst discussing the stands it’s important to note that they come with a range of different fittings on the top; we used stands with a 15mm diameter (just under) aluminium spigot with a standard tripod screw on top – this is an odd size being a ¼in UNC thread. The spigot is illustrated later on. After another quick search on eBay I found some ¼in UNC dome nuts that fit the screw perfectly.

To carry the LED strips we have gone for aluminium U-section or channel. The channel was bought on eBay ready cut to length; shop around as prices vary considerably. For our LED strips ½“x ½in channel works perfectly; the strips are held in the bottom of the channel with doublesided tape and the sides of the channel make very good reflectors. It’s very important to shield the LED strips as they are surprisingly bright; one direct look at them and you have ‘spots before the eyes’ for some time afterwards.

The challenge is to suspend the aluminium light bars over the layout from the studio stands behind the layout. We wanted the distance from lamp stand to light bar to be variable and also to have the option of tilting the light bars fore and aft to optimise the lighting effect. Diagram 1 explains this.

The support bars are simply more aluminium channels similar to the light bars. Ours are 750mm (30in) which covers the maximum width needed for all 4 layouts. All the raw ends on aluminium channels are trimmed with plastic end caps. The brackets on the light bars were cut from aluminium angle. We use M4 bolts with a plastic thumbscrew head to attach the light bars to the support bars; these look neater than ordinary bolts and enable easy hand assembly. See also the photo at the top of this article.

We found that the wedges we use to tilt the light bars are easier to position if they have a lug on them that hangs below the channel, see profile right. They are made of light plastic in case they fall onto the layout but, in practice, we would tape them in place if they are used at all; and taping is much easier with the lug. The wedges could be made from wood but metal could be dangerous to rolling stock if gravity comes into play.

Diagram 2 shows how the support bar meets the lamp stand. The support bar is cut away and profiled to marry it to a thick aluminium tube which is a close fit over the spigot. The bar and tube are glued together using Araldite (now sold under the Evo Stik brand) and cured with a heat gun. In practice the glue joint takes very little weight as there’s a hole in the extended arm of the support bar that locates over the tripod screw on the spigot. The domed ¼in UNC nut secures the support bar directly to the lamp stand. The aluminium tube has an M4 threaded hole that enables it to be locked onto the spigot with a thumb screw. The result is somewhat ‘belt and braces’ as you could do without the tube. However, this design eliminates the potential for sag in the support bar or bending of the extended arm. I actually filed a slight chamfer on the extended arm so its natural unloaded position is canted slightly upwards.

Before purchasing your LED strip you may want to work out how much light you will get. Bottom-of-the-range LED strip emits around 400 lumens per metre and that equates to a 40 watt incandescent light bulb. Bear in mind that this will be around 1200mm above the layout and directed downwards, much closer than your average ceiling lamp. LED strip with light emission over 1000 lumens per metre is available. You will also need to consider whether white or warm white LEDs are the right option for your layout; ours are white. New LED strips come with a self-adhesive backing.

If you want a starting point for LED strips on the internet search for www.wholesale ledlights.co.uk I have had some dealings with this firm, which is local to me, and they were very helpful.

We now turn our attention to the electrical side. Firstly, it’s important to understand the power consumption of your set-up and get a LED driver with sufficient power.

To calculate the power supply required you need to know:

• Length of the LED strip
• Number of LEDs per metre
• Power consumption per LED

To calculate the size of power supply (in amps) you need to multiply the length of the LED tape by the number of the LEDs per meter and then multiply this by the power of the LED (0.08w to 0.24w per LED are typical values). Then divide the value by 12 volts to calculate the required amperage of the power supply.

(<Length of LED strip> x <LEDs per metre> x <LED power>) / 12 Some suppliers give you power consumption per metre which makes the calculation easier. It is also advisable that you have around 20% spare capacity in the LED driver so it doesn’t run too hot. For the wiring, we fitted a long mains cable with an in-line switch to the LED driver, allowing it to sit on the floor below the layout at the base of the first lamp stand.

On the 12V side of the driver we fitted a coaxial in-line power socket. There’s a 3 metre fly lead that runs up the lamp stand and across the support bar; this has a co-axial plug at one end and a socket at the other. We used twin-core black and red cable as used in automotive applications, rated at 6amps. To keep the fly lead inside the support bar channel we simply use some 12mm M4 bolts in the spare holes. Every light bar has a small lead with a co-axial plug at the input end and a co-axial chassis socket at the output end – these were very fiddly to fit! The 5 light bars are simply daisy-chained together so we only needed to fit sockets to 4 of them. We loop the linking cables over the support bars for neatness and to avoid shadows. In fact, we have 2 LED drivers and 2 fly leads enabling us to run two separate lengths of lights for our OO gauge layout. You can deploy as many LED drivers as you have stands if you wish. Our layout is 600mm wide, for wider layouts you could run two or more light bars in parallel on one set of support bars.

The lights had their first outing at an open day in August 2014 so we could test them before our next exhibition in February 2015.

What a difference. The picture below shows the lights in action. The all-metal construction gives the lights a professional look and the overall illumination works very well.

I called this article Portable Layout Lights. The term ‘portable’ applies in two ways: lighting different layouts and ease of transport. For us, ease of transport matters and these lights effectively take up zero space; the slim aluminium channels and light stands slide into spaces that would otherwise be unused when we pack the layout in the truck.