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Hi Guys

Sorry for the delay in posting - all the normal reasons work, life, wife
Anyway during my break I have decided to build a new layout in my big shed.

At the rear of the shed I will have an area 3.1m x 3.4m.

With this area in mind my first idea is as attached


This layout consists of 2 levels connected by 2 helix (shelf level approx 400 above main deck)
Main Deck

Upper deck

With some free time I have been able to start on the first of my helix's.
Firstly to find out how to build one, Xtracad gives some details but in the end used "Helix Calculator" to get some measurements. calculator

So it began with cutting the rings - full rings - three and a half
Cut rings and joined with biscuits
next I built temporary frame and started spacing - not once but three times to get it right - 1. Not enough turns 2. I forgot to allow for thickness of the ply on three legs 3. Still got it wrong on one leg
Once this was right I added some spacer bars to keep from warping and it is now as you see in the photos


Next I will start the benches

Please any advise is welcome

Be good


Burlington Bob

Well-Known Member
Nice and ambitious project, but the biggest concern I would have is the grade percentage and curve radius. What scale is this, N? The addition of a tight radius curve to a steep grade is a recipe for trouble and will be compounded by longer trains. Before you get too far along you should test your helix design to see if it is workable. I have never built one myself, but the grade does seem very steep to me from the pictures. Pictures can be deceiving though! Good luck!


Burlington Bob

My idea of fun is N scale
This is my largest layout so far 1st 6' x 4', the second 4' x 3'

This layout will combine a lot of ideas I have seen

Details of the helix's are
The operational radius is 350mm
Grade of 2.1
Length of Helix 7m
seperation 114mm

I await your advice



Long Winded Old Fart
Burlington Bob is right about that Helix. It's way to steep even for HO. Most Helix's I've seen are only 4" apart for HO on ea. level. For N they would probably only be about 2" apart or less. That Helix might be OK for O scale if it was 6ft across.
Just my thoughts.:D
Your math on the helix doesn't seem right. Let see if I understand correctly. Your radius is 350mm or 13.78". The distance between the layers of the helix is 114mm or 4.49"

%Grade is defined as rise (114) over run (2 x PI (3.1416) x radius(350)) x 100 = 114 / 2199 x 100 = 5.18%

Your radius is a bit on the tight side. You need to consider what engines and cars you plan to run. Large articulated steam engines and 80' or longer freight or passenger cars may cause some problems.

A grade over 5% will not be workable as an engine will pull very few if any cars up the grade particularly in conjunction with the 350mm radius curves. A grade of 2% may not give enough clearance for all rolling stock.

If you cut a slot on your uprights at 50mm spacing so that it catches the edge of your helix subroadbed you won't need the support under the roadbed. You will need to add additional uprights on the inside of the helix.

Hope this helps!



Your valued advice has proved enlightening.
Following your advice I rechecked and my calc's and asumptions and they were flawed.
As such I attach some new calcs

Please advise if I am on the right track before I rip into any more ply


Your calculatons are now basicly right except the grade should be calculated on the track center line not the outside circumference. It bumps your grade up to 2.2%.

The larger radius will make a big difference in your operations.




Your calculatons are now basicly right except the grade should be calculated on the track center line not the outside circumference. It bumps your grade up to 2.2%.

The larger radius will make a big difference in your operations.

Had a closer look at the calculator and found it was set for G scale
revised the base equations to suit N scale and hey presto same rise, grade 1.83 (at track centre), seperation 2.75", 5.5 rings

I will do a mock up on the weekend and let you know how it goes



Progress on Helix

Wow this is proving to be a big fiddly job, but so far after some advice from those most learnned, I have designed my helix, created a jig, marked up and cut enough segments to build the rings required.

I have biscuited and glued 3 full rings and one drying in the jig, a couple of days to complete the construction of the rings and to start the assembly.

Yes they are bigger than I had originaly concieved but isnt that the same as all layouts!

here are a couple of pictures of the process line

The jig

The segments

the rings (the builders square is 600mm long)

Will post again when I have done some more

and thanks for the advise on the Helix calcs - it really helped sort it out



No one ever said it was going to be easy ;)

One thing I've seen guys really start to do is use all-thread as the upright supports for the helix levels. That way they can adjust it later if necessary without having to rebuild a whole lot.


Had a big day in the shed today, I was able to build the Helix.




I will start to install framing in the rear of the shed to mount the Helix tomorrow.

Be good




With some very cold weather here in Melbourne (Australia) progress has been slow.
I have managed to build the Helix Base unit, temporary fit the helix and build the shelf transition section.

First fit of helix onto base unit

After some fiddling around


and even some more

I am planning tocontinue with the setup of the Helix as well as continue with the shelf and main bench unit this weekend (Spring here in Aus)




This weekend proved to be quite productive, all the main bench is fitted, still needs legs and that one piece of ply in the corner (wrong size mixed in Bunnings pile and I did not check all pieces as I normally do).

Fitted edge strip to helix deck to stop(minimise) the inevatible derailment hitting the floor.

WHile the glue was drying I started the main bench units


I expect to start the second helix sometime this week(touch wood)

Happy Farthers Day to all the Dads




A bit of progress since last post, bench work inc bench for 2nd Helix are now complete.
I was able to get a printout of the layout, I laid it out to check if I had measured anything wrong but I got it right.
Ordered my flex track during the week - 75 lengths - lots of soldering ahead.
Anyway here are some pictures of latest progress

All the benchwork

The layout on the bench





Work starts on the 2nd helix this week




Hello again

Domestic duties condemed Saturday to being in the service of she who will be obeyed.
Sunday was free of other duties which allowed be to undercoat and the start laying track on the helix(1)
During the week I was able to glue together most of the rings to make up helix(2).
This week either track laying if my flex track arrives or assembing helix(2)

A couple of photoes of helix(1) with track 3/5ths layed
note the size of the 40' coal hopper


Hope all is well



I think you are doing a awesome job with your helix. Your layout will be awesome. I like how you left the inside open so you can get inside, ive seen people just have access to outside of helix and thats not a good idea. You are doing a great job.

How far is your layout off the floor and how much separation do you have between levels? Did you always want to make a multilevel layout? Or was this the only way you could fit what you wanted into the space you have available?
Im stuck trying to decide if i want to add a second level to my layout, and i cant make my mind up if i should bite the bullet and get a helix going. I have the room for a helix, im just unsure about the multi levels. I do like the idea of having double the mainline run though... Im trying to keep my layout expandable so if and when i want to add a second level, i can easily add a helix and make the move up...

Keep the pictures and updates coming. Good to have you aboard
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