Helix Design

[nachoman]

It entirely depends on what kind of equipment you are running. If it is 4 axle diesels and 40-50 foot cars, I foresee no problems with those curves or grades. Even most 6-axle diesels or 8-coupled steam engines won't have problems with 22" curves if you take it slow. A lightweight 0-6-0 may not be able to handle 8 cars on that grade.

If you are putting it in a closet, you almost have to build it before you build the layout, because once the layout is in place you may no longer have access to the closet. Trying to shoehorn a helix into a closet with access blocked by a layout could prove extremely frustrating if not impossible.