If anyone needs to simulate a welding arc, try using an old transistor AM/FM radio with a 1.5 volt micro lamp connected to the radio phone jack. Adjust the volume/tunning/AM/FM controls for a suitable flash. I put a thin film of permanent blue marker on the lamp.
I decided to interupt the flashing using a LM555 timer IC. Seven second of flashing and three seconds of no flashing. I put this circuit in series with one of the wires going to the lamp. Put a tiny lamp under a truck or car at a shop. It is really interesting. Miniatronics has some tiny 1.5 volt lamps.
It might work for a camp fire also. Red marker on the lamp.
I made my own camp fire simulator using two LM555 timers and a few components.
Sound for water going over a dam can be simulated using a transistor radio on FM set between stations. It gives a nice hiss (white noise). I made my own white noise generator using a couple ICs and a few components. Experiment with placement of the speaker under the layout. Try experimenting with speaker enclosure or no enclosure.
Experiment. Animation on a layout can add a lot.
Rich