Depends on the engine in on30 you are getting. The 2-8-0 Bachmann will not make it thru the truss bridge. The tender steps will hang up. You will have to modify the bridge to make it 1/4 inch wider. Most cars will be ok. This is on the streight sections, if the bridge is near a curve or turnout it will have to be positioned for extra clearence. Get the engine you like before you install the bridge to test for fit.
Remember that On30 means you are using O guage trains on an HO chassie and track {or specific On30 track which has wider ties and are scaled more for the o guage train size…}
The atlas code 100/83 bridges are meant for HO sized trains to pass through them, NOT O guage.
You will need a wider bridge to run your On30 stuff on, but you can certainly run you HO stuff on the wider bridges.
The buildings for running On30 would be more O guage sized buildings, while the HO versions would obviously be the smaller buildings. Good to have them able to switch out depending on which you are running.
Scenery practice is great!
DCC is a matter of choice, but I would personally go DCC, less wiring and I think less grief. Just my personal like. I won’t “do” Dc anymore at all. {except my small DC Nscale layout at Xmas until I get Nscale switched over to DCC only}
On30 modeling is 1:48 scale, not gauge (not guage either!). Gauge is the distance between the rails. The gauge of On30 models is the same as HO scale models, that is the only thing they share.
On30 rolling stock chassis are not the same as that on HO models; On30 has larger wheels, running gear, etc.
Structures in O scale have eight times the volume of HO scale ones. O scale structures will not fit on the same space as HO scale structures.
I am still in the thinking of stage . You guys brought valid points to the table!
The bridges were a concern for me . I don’t want to break detail parts off the engines & train cars . If I decide to do a On30 layout ,It will not share use with Ho trains .
Thanks again ! HAVE A GREAT MODELING YEAR IN 2011 !