Model Railroading > Can a working helix be made this way

Straight sections of board cut at a 12.5 degree angle

Jon Fink
Schenectady, NY

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No

Use 15 degree angle

-LD

Highhood Wrote:
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> Straight sections of board cut at a 12.5 degree
> angle
Dont see why not angles would tell the radius that could be used rather than trying to cut curves in it. Would be the way to do it but a friend cut mine with his NC wood routing machine and worked out great down side is waste your way would produce less waste.

LarryDoyle Wrote:
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> No
>
> Use 15 degree angle
>
> -LD

Next, depending on what radius you want, you have to figure out the width of the board that you need.

I think that you will have trouble achieving a smooth surface.



Edited 1 time(s). Last edit at 01/31/23 09:08 by ts1457.

Have you gotten as far as deciding what your clearances will be, or need to be, based on your curve radius?  That will also decide your grade that you need as well.
What about supports for each of the turns?  How wide will your wood be?, such as, will your helix be single or doubletrack, and will you use 1x3, 1x4 or 2x3, 2x4 for supports?  And what are the longest engines/cars that you plan on running?

Just a few of the questions that you will need to decide on.  Most of the time, model railroading is fun and keeps the creative juices going, even on trial and error.  Good luck!

We are ALWAYS curious to see how others build their helices as it gives ideas to those of us who haven't actually built one yet but are running it thru our heads to figure things out.

Please keep showing us progress.

V/R,

B&Oblades
aka Jason

My video on helix construction may answer some of your questions about deck-to-deck spacing (I use trimmed wood blocks, not off-the-shelf 1x3 or 1x4, for example) and side clearances or track radius matters. I used curved-cut plywood but the same block deck support would work in your situation.

I hope this helps, if TO allows external links ...

Jeff Johnston
thesugarpineshop.bigcartel.com

https://www.youtube.com/watch?v=ZdrXH--f41Y



Edited 1 time(s). Last edit at 01/31/23 11:18 by Jeff_Johnston.

Somewhere on the web there is an example of building a helix with this method, cutting straight sections of plywood and forming a helix. At one time there was a small company making pre-fab helixes in this manner, kinda lost track of what is on the market.

Agree that the clearances are an issue that's not real obvious until some time has been invested in the project. Going with the pre-fab sections would ensure somebody has thought that out, or at least identified the clearnaces.

For myself, I gave up on the stacked helix idea as being too much hidden trackage. I tried using the threaded rod idea but I like the idea of using the blocks much better. The blocks ensure uniformity as compared to eyeballing with the threaded rod. Be aware of the twist in the plywood required to make a circle, it's kinda hard to explain but becomes very obvious very quickly. What starts as an elevation change becomes a twist in the trackage if the plywood section is too long. Hope that helps.

I have used the threaded rods and will continue to do so. Yes, the helix wants to twist but you can adjust that with the threaded nuts. After I have the bottom level complete, I just add temporary spacers (short pieces of 2x4s) btw the upper levels until I get my nut and washers where I want them. I used an inexpensive, long drill bit that is about 18 in. long to drill the holes.

Victor Baird

TCnR Wrote:
-------------------------------------------------------
> Somewhere on the web there is an example of
> building a helix with this method, cutting
> straight sections of plywood and forming a helix.
> At one time there was a small company making
> pre-fab helixes in this manner, kinda lost track
> of what is on the market.
>
> Agree that the clearances are an issue that's not
> real obvious until some time has been invested in
> the project. Going with the pre-fab sections would
> ensure somebody has thought that out, or at least
> identified the clearnaces.
>
> For myself, I gave up on the stacked helix idea as
> being too much hidden trackage. I tried using the
> threaded rod idea but I like the idea of using the
> blocks much better. The blocks ensure uniformity
> as compared to eyeballing with the threaded rod.
> Be aware of the twist in the plywood required to
> make a circle, it's kinda hard to explain but
> becomes very obvious very quickly. What starts as
> an elevation change becomes a twist in the
> trackage if the plywood section is too long. Hope
> that helps.



Edited 1 time(s). Last edit at 02/02/23 17:28 by wabash2800.

wabash2800 Wrote:
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> I have used the threaded rods and will continue to
> do so. Yes, the helix wants to twist but you can
> adjust that with the threaded nuts. 

I assume by twist, as you lift the levels up from each other, it will twist.  I wonder if a fix for that is to have a oblong hole for the threaded rods so it can twist as needed when adjusting it up from flat when first assembling it.

When the plywood is elevated like a ramp the helix path would be turning to go off the side, the side of the plywood is now lower on the near side and higher on the far side. It appears that if the plywood is the right length the twist is taken up in the joint with the next section. The threaded rods were just not working for me, perhaps the sections of plywood were too wide, cranking on the nut / washer combination was just delaminating the plywood.

Mentioned this only for the helix newbie to be ready for some adjustment. For me, the hidden trackage combined with the elephant in the room nature of the helix I redesigned, moving some of the grade to the approach and second deck and then moved on.

They work for other folks and they are an interesting project.



Edited 1 time(s). Last edit at 02/02/23 15:53 by TCnR.

Delaminating the plywood? That's why you use washers wherever the nuts make contact with the plywood (top and bottom at each rod location)


Victor Baird



Edited 1 time(s). Last edit at 02/02/23 17:34 by wabash2800.

Of course I used washers.

Clive before I start my helix I need to come up buy you lunch and have you show me these helix issues.

Very much recommend visiting a Layout that has a Helix and get some ideas from them. There's plenty of folks happy with helixes, plenty of folks that built them with no troubles, there's a post just a few above this one for example. The Medford Oregon club has a helix, open Sundays.

My story was wanting to build a helix for the knowledge and experience, plenty of planning but I never did connect with a Layout that was using a helix. What I found was a helix is lots of hidden trackage, during the process I chose to minimize hidden trackage and put my time elsewhere. When I built that part of the Layout I was on TrainOrders and went through a number of construction posts, also asked some questions on TO about 10 to 15 years ago. At the time there were Layout Planning books being published, also some featured Layouts. Tony Koester was active with his Layout and the idea of a 'no-lex' was being talked about, building a grade into all of the layout and not concentrating the grade in one location. There was also talk about using helixes as the central grade seperation feature and keeping the rest of the Layout flat, lots of ideas going around.

Once again for my build, I wanted a second deck and needed the elevation change, also to change direction at the end of the room, So I stole some aisle space and spread the stacked circle into a loose spiral and left most of it in the open, kinda like following a canyon wall. Plastered over everything, including the washers and ran some trains. Lots of things have happened between then and now but I had somewhere to run trains. Also note that the second deck is a real challenge to the model credibility, not sure I like it either, maybe do it different on the next house. There's another section of track being built and some talk about borrowing a video camera on a flat car, we'll see how that works out.



Edited 1 time(s). Last edit at 02/03/23 10:15 by TCnR.

TCnR Wrote:
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> ... What I found was a helix is lots of hidden
> trackage, during the process I chose to minimize
> hidden trackage and put my time elsewhere.

My thoughts (I haven't actually done this, but maybe someday) are that the hidden trackage could be useful in modeling a given stretch of track. Most modelers try covering a sub-division or more with only a few scale miles of track. If you linked scenes with hidden tracks and built in a certain amount of delay for trains running, you could create a more realistic feel to the operation of your territory.

Yep, all those ideas are being phrased as " Layout Design Elements ', basically how to seperate or describe the different ideas built into a Model Layout design, also how it operates / functions. LDE's can be identified for a design, or used as 'given and druthers' or goals for a design, most of them are personal preferences and can be carried into a design from personal observations of other Layouts or prototype practices. In a design, those are personal choices and would also differ wildly based on available space or era.

True, you could also make the helix an invisible station stop.  For example, when that section of my layout is complete, I'm doing that for Elwood, Indiana. A passenger train operator will be required to hold the train in that section of the helix for x number of minutes. It adds a station stop that I don't have room for on the main section of the layout. (Right now, all my helices are in a 6 ft. x 6 ft. room with the exception of one 1-1/2 turn one at end of a peninsula). 

Also, since there is typically a lot of run in a helix, some modelers have used them as double-duty for  "serial staging" of multiple trains.

When complete, I'll have five interlockings on my layout and the helices will allow me time to operate trains by myself, if need be, and set-up the nterlockings as I  proceed and follow the trains. To accomplish that, as a fail-safe, a train will stop on dead section of track at an interlocking if it is not lined up yet. I'm going to wire that section of track with the home signal. But the helices should give me that extra time so that I don't have run after the trains.

I also have two additional rooms in my basement at my disposal, and one of them will be for staging. I plan on adding another helix in there to connect both levels for continuous running so I can railfan and operate the interlockings as I mentioned above.

Victor Baird



Edited 1 time(s). Last edit at 02/03/23 12:05 by wabash2800.

No, during construction the subroadbed wants to twist, making it not level from side to side, When complete, your railheads must be level with each other even with the track going up or downhill. With the nuts, washers and threaded rod, plus the temporaty spacer blocks, you can adjust any twisting during construction with threaded rods on both sides of the subroadbed. Superelvation or countersuperelvation on a model railroad helix is not your friend! A helix can be the best section of track on you model railroad if you do it correctly. I once had an engineering friend who thought countersuperelvation on a helix would help keep the trains on the track! At the least, it is not necessary, and at the most it will cause serious issues!

Victor Baird


SPDRGWfan Wrote:
-------------------------------------------------------
> wabash2800 Wrote:
> --------------------------------------------------
> -----
> > I have used the threaded rods and will continue
> to
> > do so. Yes, the helix wants to twist but you
> can
> > adjust that with the threaded nuts. 
>
> I assume by twist, as you lift the levels up from
> each other, it will twist.  I wonder if a fix for
> that is to have a oblong hole for the threaded
> rods so it can twist as needed when adjusting it
> up from flat when first assembling it.



Edited 2 time(s). Last edit at 02/03/23 12:00 by wabash2800.