Smoke Jacks?? (updated)

First all, let me say that I'm not even 100% sure that is what they are called. I could have sworn that I read it somewhere, but not really sure now.

I'm looking for details on the smoke jackets??? (aka ventilation system for roundhouses to get the smoke out of the facilities). I'm nearing that point for my model but just am not sure how to go about constructing it. I see in some pictures that they looked to be rectangular in shape, maybe about 2.5'wide and 5' long, but I'm completely just pulling that out my backside. Does anyone have the dimensions of them?

Also, was there a standard way they were installed in the roundhouses? Were they in the front or in the rear or both? I have seen images and documentation showing both really...so I'm VERY confused

Any help and documentation/photos would be greatly appreciated.

Craig
Somewhere up in NoCo



Edited 1 time(s). Last edit at 08/16/2010 07:18AM by Samart.