Hi Daryl-
I just ran the tape measure around the aisles since it was awhile ago I finished that part of construction.
I naturally wish the aisles were roomier, but O scale radius minimums become an issue if the aisles are widened out. Less railroad? Thought about it, but chose to accept one pinch point with wider spaces on each side for passing. That spot is 26" for about 4'. Folks just wait to pass as needed. I don't know how often that occurs in an op session, but no one complains. That spot is at the far right end of the paper mill, near the Bayfield double-crossover, and across from the start of the grade at Union Gap, since you seem to know the trackplan.
Generally the aisles range from 30" to 42". We find that even with 20 folks in the basement, they're spread out moving trains, eating/talking in the crew lounge, etc. and don't clog the aisles too much. Sometimes we'll get a knot, but no big deal. If ops were prevented from happening because people were stationary there, that would be big deal.
Where there's switching, I tried to make the aisles as wide as possible with the end of the papermill being the exception. The Millport aisle naturally gets the most traffic, literally. But I was able to make it 4' or more wide for the 5-7 people who come and go. And of course, it's under the garage and is walls are about 39' end to end.
As you can see on the Construction page, I prefer having a free flowing front fascia edge vs. a table/plywood edge where possible. This can then mimic the rail line and open up a few inches here and there to widen aisles. It helps. Plus it's more pleasing to the eye. The various photos can help.
As Bob mentioned, the Kayford Branch is by necessity narrower in aisle width with it being more in the 30" range. But the Kayford rarely has more than 3 operators in there at one time. And it's long serpentine aisle dead ends, is "dark territory"- literally and figuratively, so by nature it requires cooperation among the crews. I pondered omitting it altogether for more aisle space in the mainline area, but I'm sure glad I didn't. Crews seems to love leaving the flow of CTC territory and heading down into the hollers.
One other aspect to compensating for aisle width is traffic flow. When I plan op sessions, whether by time clock or scheduled order, I space out trains when possible so as to not occupy the same space simultaneously. Example: I don't have the papermill switch job run until the Penn-Central and B&O trains have passed thru and done their switching of setouts/pickups. Likewise, I plan the order of coal switch jobs in the Kayford.
Last thought. Limit the # of Big Macs allowed before ops.
Hope this helps,
David
