Bnsf, the others have given good links. I just wanted to add that I built mine out of two layers of 1/4" plywood glued together. I essentially cut half circles and offset the gaps 1/4 circle. It made for very smooth connections between sections. Make paper templates and lay them on the plywood sheet in several different ways. You'll soon discover the most efficient way to cut.
Karl
The mind is like a parachute. It works better when it's open. www.stremy.net
tgindy Check out these two Kalmbach PDF-downlads and cover pics... [2] Guide to helix & staging design (Vol. 2).
Check out these two Kalmbach PDF-downlads and cover pics...
[2] Guide to helix & staging design (Vol. 2).
The helix shown in this pic is mine. It is almost exactly what you have described in terms of specs for your helix. I used 1/2 ply as road bed and found that 3.75" between rail heads produces roughly a 2% grade in the helix at 30"/32" radii.
I used a trammel to lay out the sections on a 4 X 8 sheet of plywood. I laid them out in quarter turns and cut them out on a band saw. You can get a surprising amount of pieces from one 4 X 8 sheet. I laid out each rotation on a table with a circle pattern drawn out for one rotation. I carefully cut each group of quarters to fit the pattern and then glued them up in place using a tape measure to keep everything in line.
I used code 100 flex in the helix. I laid it out and soldered it on the table before installing it on the helix. I then spent lots of time soldering filing and checking to make sure that the track joints were perfect on each level of the helix before adding the next level.. It has been in a few years now and works flawlessly.
Guy
see stuff at: the Willoughby Line Site
[1] Guide to helix & staging design (Vol. 1).
And the most recent "How to Build" special issue...
[3] How to Build More Layout in Less Space (just-published).
Conemaugh Road & Traction circa 1956
Jeff Johnston has a very good two part video series posted to YouTube. Search YouTube on "helix construction" and/or his name.
Recovering former former model railroader.
i have an ho scale layout that is going to need a helix to take it from the upper bench to the lower bench. I was wondering if anyone had any good websites that would have a step by step instructions on how to build a good strurdy helix. the radius i am planning on going with is 30-32 inches and the distance i need to travel is 20 inches. Ide like to know what the best distance between levels would be. Also i need both entrances to come out the same direction from the helix. Any help would be great also if anyone hase some pics of paterns to get the most out of each 4x8 sheet of plywood with a 31 inch radius that would be helpfull too. THanks