molten iron

I'd suggest very closely spaced LEDs and a diffusing translucent layer between the LED's and the clear silicon top layer.  I have done this on a smaller scale with flickering firebox installations, I use four or six flickering LED's behind a plain sheet of #20 white paper to diffuse the point of light.  I also sand off the front of the led's flat to further diffuse the point of light, another thing you can try.

There are some high density LED strips that have very closely spaced LED's that might work well in this application as well. Here's an example from my LED box...

If you want to get fancier, you could look into the individually addressable LED's so you could impart some motion to the stream of molten metal.

Try shining a few LEDs into the top of the silicone. It should act as a light pipe and give a nice, uniform illumination. If it doesn't work with silicone, it will certainly work with clear styrene. You should be able to melt a few sheets into shape.

Get some electroluminescent wire.  I comes in various shade and it might be possible to "weave" red and yellow together to get the right color.  

I'd look at something like a translucent sealer to cover it.

I probably could come up with a way to make it "flow", but my thinker thingy is going to go to bed for a while first.

I don't know if anyone else noticed... but,

HOLY CANOLLI PARRGUY!!!  That is one nice BLAST FURNACE!!!

and, WELCOME TO OGR!!!

The Lehigh & Keystone Valley HO layout in Bethlehem, Pa. looks like they used strip LEDs for the molten effect. It looked quite good.

Add a little bit of flicker to them and they'd look really good.

@parrguy that's a heck of a mill you got there!

I will be very interested to see what you try here because I'm working on a layout that will feature blast furnaces. I also aim to animate tapping the furnace.

I planned on using individually addressable LED lights and something like hot glue to get the light diffused. The electroluminescent wire @Forty Rod suggested above looks very like they have potential but I don't know anything about them. I wanted to get individually addressable LEDs to be able to simulate the iron running along when the furnace is first tapped and the wire might not let me do that. We'll see. I'm still working on the structure at the moment anyway.

Thanks everyone !!!

This thread is a real BLAST !!!

In Run 306, there was an article entitled "Hot Metal in Steel City" that featured a sub-article on "Modeling Molten Metal" that discussed a technique using LED's and some bottled tea wrappers that looked pretty convincing.  Might be worth a look.

On the videos I've seen of blast furnaces,  the iron is one solid stream from tapping till the mud gun closes the hole.  Motion is imparted by the movement of pieces of Slag floating on top of the iron.  INMO if you want to mimic this movement,  use GRJ's  idea of  closely spaced LEDS  but couple them to some sort of  "chase lighting " module set at the slowest rate possible for effect. Something like is used on theater marquees.

BTW great looking blast furnace complex.

As for figures,  you can get any from number of makers suitable  construction workers but nobody makes steel mill specific figures.  I'm thinking of using firemen that are modified and painted to resemble someone wearing "silvers".

I would like to add that to my blast furnace