Functional lanterns?

Since I bought the beautiful EX REE hoppers, I wanted to replace the tail lanterns out of era for me. So when I saw that REE released lanterns of years 60 / 70, I wanted to fit them to these hoppers. Indeed, their lanterns are illuminated by a light guide, the LEDs themselves being soldered on a PCB located under the chassis. The new lanterns have an identical light guide. The replacement was supposed to be immediate, and it was. But…

… but the new lanterns are shorter, and so the light passes more underneath than through the “glass”. Moreover, the guide has no 45° beveled end, so that the light is not reflected in the lantern axis, which is frankly a bit stupid! As a result, virtually no light is visible where it should be.

Hence the idea of ​​putting LEDs directly into the lanterns. Obviously, there is not much space, but after checking, I find that a 0603 CMS LED (1.6 × 0.8 mm) may be suitable. The whole problem is to find how to introduce it into the inside, which seems well filled.

Opening of the lantern

I managed by chance to extract the red “glass”, which in fact is transparent and covered with a layer of red varnish, quite fragile. I will later find that the metallic paint is also fragile, on white plastic, ideal to be translucent. Too bad, isn’t it?

So to extract the “glass”, it is necessary to leverage inside — passing by the base. To do this, I made a tool from a Ø 1 brass rod, the end of which being cut into rectangle, then chamfered. It would be simpler to directly use a brass or nickel silver rectangular rod of 0.8 × 0.5 mm. The bevel is about 1.5 mm long.

Extracting tool

The “glass” appears as a small cap that penetrates almost to the bottom of the case. Almost, but not completely, which allows to insert the tool.

Disassembled lanterns

This part is very small and difficult to handle. I stick it on a piece of adhesive on which it will remain for the next operations.

It will be necessary to shorten this glass by the back to make room for the LED. I place it in a ø 1,6 hole drilled in a 0,5 mm thick plate. Personally, I used a 0.8 mm piece of epoxy of which I reduced the thickness by milling. After turning this plate upside down, just file what juts out the other side. And this is where the red varnish begins to leave… Not too serious, since the LED will be a red one.

Mounting for glass planing

What if REE proposed these lanterns unmounted, with a shorter glass, and no useless light guide? And in a less translucent material? Well everyone could easily do what I am doing painfully, by directly mounting a pre-wired LED, and this in just a few minutes…

REE lanterns ref. XB-502,
about 8 € for 6 pieces — price 2015