What you are describing is an elevation change from thick HO cork to thinner N cork. There's no problem doing this if you consider it as being a very low hill that requires a vertical easement at both top and bottom to keep things from uncoupling or your coupler trip-pins from hitting track or ties. No big deal; just taper the height slowly, and test both long- and short cars, and mixed together.
As for double-heading. I remember an article in a magazine some years back that talked about it in a DC environment. Basically, you can do it if your power supply can handle the current, and both locos run at the same speed. If mismatched, one will work harder than the other and overheating may result if the match is not close. Running long distances means the match needs to be better.
George.
I do this all the time. I run about 12-15" beyond the turnout using the HO roadbed. I then start laying the N cork roadbed. Get yourself a Stanley 'Surform' tool and just sand a nice gentle transition down to the N cork. Then clean up the mess! I takes about 5 minutes of work. If you have something like a 'Mouse' detail sander, put some 60 grit sandpaper on it and it will take you about 30-45 seconds to produce the taper. All of my sidings 'drop' down off of the mainline and there are no derailments with this method.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
Just as a matter of information, even though you may have enough power to double or even tripple head locomotives, you may not be able to successfully do this because of the type of engine you have. Some locomotives, for example the typical entry level Athearn models, have one side of the motor grounded through the engine frame. When coupled to another engine of the same type, it is possible to get a short circuit through the couplers. This is not an insurmountable problem, because there are ways to isolate the frames. One way to do this is to use non-metal shank couplers between the units.
If you have this problem, that would be the subject of another posting. And it is a topic that has probably already been discussed. I only mention this so that you can be aware of a possible issue and not be surprised.
Regards!
to the forum chpthrls.
For your roadbed transition, some #36 sandpaper wrapped around a block of wood will do the trick in about 30 seconds.
For doubleheading locos on DC, they should run at approximately the same speed throughout their speed range for the best results, but even grossly mis-matched units can be run together, although it won't be much fun. It's nice, too, if both locos start at the same throttle setting. I regularly doublehead both steam and diesels, and steam with diesels, too. If you wish to run helpers, where one or more locos are on the front of the train and another one or more are pushing on the rear, then it becomes more important that all locos start at the same time and that their speeds are fairly closely matched. Most good-quality locos of the same type and from the same manufacturer should run well enough together to be doubleheaded.
Wayne
Marlon
See pictures of the Clinton-Golden Valley RR