Issues in layout Design – Helix The material I am about to use comes from two sources, both by Doug Gurin. The first source is from the Layout Design Journal, Spring 1996 LDJ 14, an in house magazine from the Layout Design Sig people of the NMRA. This source may be difficult to get a hold of, if you are interested. My second source is from MRP (Model Railroad Planning) 1997 – a magazine put out once a year from Kalmbach, the people who bring you MR. If you are interested in this material, I recommend you attempt to get the 97 MRP or order a reprint from Kalmbach. The article by Doug in MRP will help you avoid some mistakes and consider design issues. My purpose is to offer an introduction into helix form and function for the advanced beginner who may be considering a helix. First, what is a helix. A helix looks like a giant slinky pulled open which runs trains on the slinky so that the train can gain or lose elevation in an area that is smaller than you would need with other design methods of elevation gain. Except this slinky in HO could very will have a diameter of almost six feet across. So your train goes up and down the slinky to change elevations and decks. So if you have two decks, one way to gain elevation is to install a slinky (helix). Second, should you have a helix? There are those who like em, and those who don’t; just as there are folks who like double or triple decks, and folks who don’t like them. Of those who have built layouts with helix’s, some have vowed not to have one on their second layout, others would opt to change how they built the helix, and how they used it. So a helix is a controversial topic. The first problem with helixes is that they eat up a lot of room and are often difficult to disguise; almost universally becoming a mountain. So you come into this room with a wonderful multi-shelf layout, with incredible scenery and structures, all well detailed, and there right in the midst of this wonderment is this large blob. But helixes can be hidden, they can go into another room, a closet, or as one person I have seen, a false wall installed to separate visually the layout and the helix. What you should know is that if you are going to install one, include more than just a mainline track; if you can afford it and have the room, maybe even three tracks across. The reason I say this, is a helix can also serve as staging. So one track is devoted to the mainline, and the others for linear staging. The reason I mention expense is that a 20-inch separation in HO between decks calls for approximately 80 feet of track. If you triple track the helix, you’re looking at 240 feet of track (this is a good location to use the cheaper Atlas flex track as no one is going to see it). The helix can have different functions. One chap I know has installed a helix between decks strictly as a staging helix, with no functional mainline running it. So trains are staged in the helix and brought out as required in a linear staging fashion. His trains are on average ten feet long, so figure out how many trains he can have staged in this area. Another purpose and the most popular place to install a helix is in the “middle” of a track plan. So the trains start at one location on the first deck, crosses the deck, goes up the helix, and crosses the second deck. This is considered one of the worst ways to use a helix. Why? Well let’s go back to a single tracked helix, which provides elevation gain for a 20-inch separation between decks. If your total mainline run, including the helix is 160 feet, your train will spend about the same amount of time out of site as running the visible mainline. A better solution is to have a mainline RR feed a branch line. So if you take the same configuration of the helix in the middle, in essence you almost have two separate lines each running on their own deck. Occasional interchanges of cars and trains via the helix occurs, this configuration becomes easier to enjoy as all the trains aren’t eating up vast amounts of time in the helix. The easiest way I have seen – and about the cheapest – is to use to overlapping half circles of plywood, joined at the overlap. Tall wood legs go up the inside of the helix, usually around 2 by 2’s. The “slinky” plywood circles are attached to the wooden legs using L brackets. Once the outside of the helix is sceniced with hydrocal, you have a very strong helix. It is HIGHLY recommended you install track and wiring as you go; you could regret not following this advice.
Have you seen diligentman's thread on helixes, "Helix, Would you do it again?" We're discussing helix pros and cons and have pictures of people's work. Looks like you would have lots of good info to contribute. Dave H.
FWIW... Here is a pic of my helix. Of course I didn't follow any of the rules, but it works for me...
Hutch: Very nice. Any suggestions...Anything you'd do differently if you were building another? Dave H.
An excellent source, and not too difficult to get as a back issue from the Layout Design SIG. http://www.ldsig.org/publications/journal
three through most of it except the bottom two rings where it goes into the under bench yard P.S wasn't tring to show off or upstage anyone :embarassed:
Mr. Train, what method of splice block are you using on the helix? I see the splices on the top subroadbed, but darned if these old eyes pick up anything below that first level. Michael
RGW I pm'd you as for any one else that is wondering that same question I will try to back to this soon with more info later. Please stand by.
