Of Underframes...

I've been letting my brain wander ( it like that while I'm on the bike or doing crap tasks at work) on wagon topics, and more precisely on how to model the underframes. As my brain sees it, there are 2 main alternatives.
1) An RP'd underframe cast in one piece. Pluses are the incredible amount of detail that can be incorporated. Minuses are that someone with the necessary know how and skills has to be chained to a computer till its sorted out (oh, and researching the incredible level of detail required). also, a new master has to made fro each different variation 0n the underframe.
2) Etching. This would use an inner frame with cosmetic outside bits. pluses are the level of flexibility possible with this approach. Minuses are having to build the damn things right.

My brain has come down in the 2nd camp. The position has been strengthened by the discovery of the following web site ( its in 4mm, but the ideas are pretty good). http://www.mousa.uk.com/Cat/OLCat4/index.html

What does seem like a good idea is for separate W irons for 4 wheeled wagons( http://www.clag.org.uk/bb-w-irons.html). While I don't think I'm going to have a go at the springing, the flexibility of this system shows a lot of promise. Cosmetic solebars and axle boxes can be added, and the wheelbase is simply sorted by gluing the W irons onto the chassis at the correct distance. This can also be extended to wagon bogies (again, http://www.mousa.uk.com/Review/bogie.html for more details). From memory most of the variations can be modeled with 3 wheelbases; 5', 5'6" and 6'. What is even more handy for modern image modelers is that the wagon bogies are almost identical (to all intents and purposes) apart from the springing and so can be represented by 1 bogie.
Another plus is that I think I can probably handle the 2D thinking required.