Paula - you just said that your blind chin has a problem navigating a CN, "I have a blind chin in a CN (over 5 feet) and he's a problem at navigating it."
Yeah, that doesn't make any sense at all. Thanks for pointing out my typing error. To be clear, what I meant to say was
I have a blind chin in a DOUBLE CN and he has absolutely NO TROUBLE AT ALL navigating up and down and all around. I probably would have seen it and edited my post right away if it hadn't been moderated because I have so few posts.
I understand what you're saying about the shelves and the 20" limit, thanks for clarifying. I don't think the emphasis is on flat floor space for chinchillas, since they are naturally climbers, jumpers, etc, so it's always been my understanding that taller rather than wider (like for guinea pigs and to some extent, rabbits) is actually usually preferable.
I know there are some awesome DIY chinchilla cages, but I've not seen one that I'd feel comfortable putting a chinnie in that didn't have a wood/melamine frame and given my person experience with C&C and shelving type DIY cages, I just couldn't in good conscience recommend to a new owner the C&C or shelving option because I just don't see how it could be made sturdy enough unless you're able to weld them together.
As for the comment on the five foot fall - tall cages have perches and ledges that chinnies just love to jump from, ricochet around, etc. The only way a chin could fall from 5 feet would be if he were allowed to run around on top of it with no guard or supervision with the CN/FN cages. Just wanted to clarify that - if you haven't ever seen the cage up close it might not be clear how the setup could be done.
Anyway thanks for clarifying and pointing out my error, and I'm glad the shelving seems to be working for your chin. I am generally the first to recommend a C&C or shelving type cage if it can be done safely - I've got a great deal of experience with them and highly encourage folks to use them when appropriate. For a chinnie, though, there are just too many potentials for injury or worse when you have a cage that can't be made terribly sturdy and has enough plastic components that it could be dangerous, too.