The Märklin Diary of a 44 yr old Kid
Using fibre optics to replace simulated rear lights.
Editor's note: The following is a re-write by John Symons of his 6/14/2006 posting on the
B&G Yahoo News Group
, he sent me pictures of his work.
Posting:
I have just finished adding rear tender lights to 2 P8 Baden loks and oneBR38.
They are all basically the same lok with exactly the same tender construction.
There are 3 painted lights on the back of each tender and I must confess I have only converted the lower two on each as the third light is actually above the tender housing whereas the lower two are integral to it.
I had been thinking of ways to do it including LEDs until a clever friend of mine suggested fibre optic cable.
I got some 2mm fibre optic cable from a supplier here in the UK.
Taking the tender body off reveals 2 metal plates that are used for weight.
They are identical and have 2 holes in them, one of which fits over the locating peg moulded in the tender chassis.
The second is not used and I used this to hold the bulb holder.
There is also a slight gap under the plates when they are in place that allows for wires to run under them.
I used a bulb holder from a 60903 kit that I hadn't needed in another conversion.
I found that with one turn of insulating tape around it, it fitted perfectly in the smaller of the two holes in the metal plates.
Incidentally I used double sided tape to hold the 2 metal plates together and also to fix the plates to the chassis once I had fitted the bulb holder.
It just stops the plates moving around when you are working on the wiring etc.
I drilled out the two lower painted lights using a 1mm drill first to get it exactly in the centre and then a 2mm drill to get the final hole size.
I then fitted a small piece of the fibre optic cable in each hole cutting it off level with the outside using very sharp pliers.
You can see from the pictures that I managed to gently bend the Fibre Optic Cable around the lugs in the tender body that hold it to the tender chassis.
If you want to bend it any more than that you will need to carefully and gently heat the cable before bending it.
A little enlarging of the hole at the front of the tender was needed to allow for the wires for the lights to run in plus the speaker for the loksound decoder (optional of course) and it was done.
The first one took about 30 minutes as I sorted things out but the other two took about 15 minutes.
The result is, as far as I am concerned, very good.
Now, if I can find some way to get that third light illuminated?
If you need anything else please ask.
Images and content are Copyright 2006, John Symons
John can be reached at: 
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