The question of making modle diesel locomotives produce black smoke has been floating around for some time. I think I may have found a solution. Cintronella oil makes black smoke when burned in tiki torches. However, cintronella is very flamable and there is the danger of it simply igniting in a smoke unit. O-Guage Railroading cautioned against using paraphin-based lamp oils for this very reason.
My advice for anybody looking for black diesel exhaust is to bench-test this one in a safe environment (ie smoke unit hooked up to a power supply with a fire extinguisher handy). Who knows, even if the smoke isn't black, cintronella does smell nice and keeps bugs away. Hope this helps.
Modeling the Pennsylvania Railroad in N Scale.
www.prr-nscale.blogspot.com
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