Thanks Tomikawa I thought HOn3 ran on N scale track before but I guess I had it backwards. I guess I'll use HOn30 then. I was expecting to scratchbuild everything. I don't mind, scratchbuilding is actually one of my favorite parts of the hobby.
Matthewg, I have seen the K-27 ads and the MR review and thought it looked nice but it would really look out of place in a heavy industrial setting.
You might want to consider using 30 inch gauge for your mill haul railroad. While HOn3 is feasable and can be reliable, most of the available rolling stock is patterned after Colorado line-haul prototypes - locomotives too big, rolling stock too light and of varieties not common in steel mills (cattle cars, drovers' cabeese...) OTOH, HOn30 would allow the use of readily available N scale mechanisms as kitbash bases for more appropriate prototypes (or protolances, since you're freelancing.) Present-day N scale is at least as reliable as HO as long as track and wheels are kept clean.
Hand-laying specialwork is not particularly difficult, especially if you are going to imbed it in pavement. You can make use of single-point (trolley-style) turnouts, which would be appropriate for the kind of low-speed operation you propose. In his book The Classic Layout Designs of John Armstrong, The Master Designer has one layout (article titled To Hardscrabble, the Hard Way) which is dual gauge and includes diagrams of just about every kind of dual-gauge turnout and crossing.
Since steel mill rolling stock is highly specialized, you would probably have to scratch build most of it. Using common N scale 'ingredients' (steam or diesel switcher mechanisms, high-capacity freight car trucks, flat car bodies...) would be simpler than trying to assemble something appropriate from HOn3 parts intended for low-capacity early 20th century rolling stock. (Trust me on this. I'm faced with trying to assemble some highly specialized 10.5mm gauge rolling stock to match locomotives I already own. It would be MUCH easier if I could use 9mm gauge, but narrowing the locomotives' track gauge is not an option.)
Chuck (modeling Central Japan in September, 1964 - with handlaid specialwork)
I have been thinking about incorporating a HOn3 (or HOn30) narrow gauge line on my CA&S layout for hauling ingots. Since so many steel mills were served by narrow gauge in my modelling era (1940's) I thought including it would ad to the realism of the layout. I have always wanted to try narrow gauge anyway, so I thought this would be a good chance. However, I'm not yet sure of the decision yet for a few reasons and I need to have the plan set in stone (Rockite Cement actually) soon. These rails will lead into the teaming aisle of the open-hearth and will be embedded in concrete which will be modelled with Rockite Cement.
Some good things about narrow guage are that it would allow me to install two tracks in the teeming aisle and make operations more complex. I'm thinking that the turnouts joining dual gauge narrow gauge and standard gauge will need to be handlaid, a skill I haven't learned, but it's always good to learn something new.
I'm still not sure about the operating reliability of HOn3 (or HOn30) and I don't think I have ever even seen models of this gauge in person so any suggestions or comments there would help. Also I would appreciate any hints on handlaying.
One thing I don't have is a source for models/mechanisms in this scale. thanks in advance to anyone who can give me one.
I could always stick to standard gauge only, but narrow gauge has always interested me and it fits the prototype*. Thanks for any help!
*Since the CA&S is freelanced and has no real prototype its prototype is any steel mill. The way I see it is that if it existed in the real thing then there is no reason it can't exist on my layout.