The faux fire in the pit is done. It's not as bright as I once hoped so it would cast ambient glow on other things in the display, but that's just fine. I love the subtle hot ember effect it ended up having. It's a nicer atmospheric detail that enhances rather than calling too much attention to itself.
Since we last left off in Part Two, I added more blobs of expanding foam to look like coal and (after drying) base coated the whole mound in flat black. Once the paint dried, I placed orange X-mas lights inside (the top of mound is removable). They were not arranged in any special way, just evenly spread out with small drops of hot glue on the strands, here or there, to keep somewhat in place.
With the X-mas lights on, I used a rotary tool to sculpt the foam were needed so it looked a bit more natural. I also gouged out spaces between blobs and scraped off more opaque painted areas to let the glow shine through better.
I drilled hundreds of random small holes everywhere, especially in the top to let heat escape. The holes also let the light shine through completely unobstructed giving the fire extra highlights.
I wanted the coal mound to look somewhat believable during the day when not lit up, so I added ashy texture and detail to it. A combination of gently sanding with a fine grit paper and dry brushing on a light grey acrylic wash worked. I would of literally spray glued on real ash had I had some handy.
The internal glow has a simple flicker effect using the old Disneyland Imagineering trick of adding a fluorescent light fuse to an extension cord. I'm not going to try and explain how to do this in fear of not explaining it well. I learned how from an old co-worker who was a professional effects person. DON'T TRY until you've researched it thoroughly. Electricity can be dangerous.
Here's a brief video of the fire effect in action.
The cauldron sits on top very well balanced and solid without needing to secure with glue or screws. We'll see if that remains the same once I add Grool the Zombie inside. That's next.