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TH&B Hamilton

New Member
I am currently preparing to build my second layout. It has been 4 years since I moved to my new house and finally, I have been authorized to commence construction.

My layout room is 8 feet by 11 feet. I wish to build a two level shelf style layout, with...yes that is right... a helix.

I read about an elevator you can build, but I would like to try a helix.

Now I need some advice, direction, and help. How do I build a helix. I am having a hard time locating reference material online or in books. Also is a 36 inch radius too small.

Looking forward to your responses.

grove den

naturally natural trees
2 X helix???

Do you want to make two or just one helix??;)
BTW of course first: welcome to this !very! friedly forum:)

I look forward to any replies you get on this topic, as I would also like to understand the basics involved in the construction of a helix. But how do you plan to return trains from the upper level to the lower level? Are you planning a bi-directional pair of tracks on one helix?

TH&B Hamilton

New Member
My layout design is point to point. When my train departs from the lower level which will be the Aberdeen Yard, Hamilton Ontario (or a reasonable facsimilie) and arrive at the upper level Mohawk Yard, Brantford Ontario. The train will switch out cars at different industries, then return to the lower level.

Steve B

Why not use the four walls as a helix to save space

With a 36" rad you will eat up a huge chunk of the room, my garage is 8'8" by 17' and i have gone round the walls, or should i say am going round the walls when i'm done, this gives me ample room in the middle for a perninsular lengthways, there are no loop's in my track and i have a gate that swings out to gain easy access. It is a single track which crosses it's self on the upper level then this is where i have a down grade onto the lower level followed by an up hill grade back onto the top level, sounds very confusing but it's not that bad.


Lake Shore Lines
36" is definitely a good curve. especially if you have large equipment. I haven't built one in awhile, and the last one measured 6 X 8 feet because we incorporated some straight sections with nearly 5 revolutions. I does take up alot of space. You will need at least 7' x 7' counting overhang for the cars and some kind of enclosure and that will be single track with sufficient spacing between levels to clear your highest car. Just like a tunnel entrance. Usually on a 2 1/2 percent grade. I used to have a formula at home and will have to check tonight to see if i still have it which computes the rise. It was in an old MR. Depending upon the height diference between the two levels, you might just want to consider building it into the length of the layout itself. Obviously, the smaller the equipment, the smaller the curve. Don't know the period of time you are modeling. You might be able to get a way with 26" radius curves. That would reduce the size by almost a foot and a half.

Bob A,


Master Mechanic
I think Steve has so far given you the best advice.

Keep in mind that a helix will eat up a lot of real estate. You mention using 36" radius. Unless this is separate from the layout area, you're going to be using at least 7'x7' of this area, just for the helix, at the 36" radius.

Given the size of the room, there is no reason for you not to be able to have that line going around the perimeter of the layout, or even twisting in and out of the scenes, giving you an excuse for some spectacular bridges as the line wraps up, or even down, to the second level.

I think if we had a better idea of what you want to have in the layout, a rough plan would even do, we could give better advice.


Master Mechanic
Forgot to mention this.
Xtrkcad, a layout design program, is a free download from Sillub Software at It has a free helix calculator included with it.

TH&B Hamilton

New Member
My mistake, I meant an 18 inch radius to which would be a 36 inch diameter requiring I would think at least 42 inches of space. I like the idea of using the wall however my furnace and water heater share the same room.


Master Mechanic
Using an 18" radius for the helix is possible but the grade will be a minimum 3.2% with 3 turns of the helix. And that's just barely enough for clearence for the cars and locos between the levels of the helix. The track length in the helix is almost 400" long. This grade will greatly cut down on the number of cars that can go up the helix. Not only due to the drag caused by the grade but also for the drag caused by the constant curve. If you go to 2 turns of the helix, the grade goes to almost 4.5%

If you could go to a wider radius there will be an improvement in the grade but track length will increase as well.


Coal Shoveler
18"r for the helix is the bare minimum, and pretty much limits you to short cars and no full-sized passenger cars that have body-mounted couplers. If you can swing 22"-24", try that.

The main key is that you want smooth trackwork inside the helix so you won't have derailments and other problems which cause you to have to get inside to rerail. Remember, unless you have all-around access, you're not going to be able to reach 36" to fix a problem; most folks climb inside the helix to do that. So, if you're a big dude.....

There was an article a couple years back which talked about building a helix using angled sections of wood. I think it was in '04, the latter half.



Wyoming native
Here's a shot of my helix (not quite finished):

(Sorry about the oversized photo - that's what's on my website)

My inner track radius is 36". The helix is a suspension type - the support frame is attached to the ceiling,
and threaded rods extend downward to support the tiers.

This will tell you more about it's construction: - Behemoth Helix.htm

A couple of cautions:

With a relatively small radius, it will be easy to "stringline" a train on the helix grade, that is, pull it off the
track towards the center of the helix if you start suddenly while on the uphill climb. The longer the train,
the more prone you are to doing this. Car length also has a significant impact on this tendancy - small
ore jennies have little tendancy to stringline, but full-length passenger cars are VERY succeptible.

Hexices use up track at a prodigious rate. In my case (extreme, I admit), I went through TWO 100-piece
boxes of Atlas flextrack (four track helix). With all that track in the helix, that means your train will be in
there for a significant part of its total running distance on the layout. That was a downside I chose to
accept; think carefully about it before you proceed.

If you do decide to go ahead with the helix (and even if you don't), remember to share some photos
and stories of your progress!

Good Luck!
Last edited by a moderator:
The Helix To knowhere! haha

Ive been looking at doing a around the walls style to change from the top level to the bottom level, im looking about a 4% grade, thats 4" over 8' its gonna take all four walls (9'x9.5') to get it from the the bottom, but thats okay!

BTW that helix is impressive!



Here's a picture of my helix while it was under construction. It has a 50" diameter and rises 3 revolutions. My only thought is that the roadbed uses up a considerable amount of wood and that you should plan the cuts very carefully as not to waste plywood or 1x lumber. I had some difficulty (trains uncouple) where the slope of the track changes when it exits the helix and returns to level running.



Diesel Detail Freak
Looks nice Bill! I guess I'll be lucky with mine then, nice the grade is a continuum of the whole layout.

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