Need help in finding info about building a helix - single or double. Appreciate anyone directing me to an article or articles concerning this. Thank you.
Ponce
The easiest you can do is do a "search" for helix in the search box on the right side of the screen. It should answer many of the questions you have.
Here is one way: suspending playwood roadbed with threaded rods. Be sure to lay/test track as you progress with the subroadbed while you have complete access. With a less-tall helix, I presume supporting the rods from below would work if you wanted track to be visible on the top track. Using threaded rods allows minute adjustment to grades. A short digital level showing percent-of-grade is great for getting a consistent grade.
Be aware that long-arc curves increase the effective grade. The rule-of-thumb for HO is 32 inches divided by radius in inches, divided by 100. Thus a 32-inch-radius curve effectively increases the grade by 1 percent, and a 3-percent grade effectively becomes 4 percent. And so on.
http://groups.yahoo.com/group/CMRSC/photos/album/1246615307/pic/list?mode=tn&order=ordinal&start=21&count=20&dir=asc
Mark
Ashline Designs markets wood kits for building a double track helix with 2% grades with track radius of 22 or 26 inches for HO; they also make N-scale versions.
EASY-HELIX, LLC <link> makes modular kits for building a circular helix or an oval with easement curves for entrance/exit.
There is an earlier thread here on actual calculations for a helix.
Co-owner of the proposed CT River Valley RR (HO scale) http://home.comcast.net/~docinct/CTRiverValleyRR/
Download these two PDF Station books and voila...
$8.95 - "Guide to helix and staging design"
http://kalmbachcatalog.stores.yahoo.net/mrpdf032.html
$8.95 - "Guide to helix and staging design - vol. 2"
http://kalmbachcatalog.stores.yahoo.net/mrpdf049.html
Enlarging the two covers is also enlightening!
Conemaugh Road & Traction circa 1956