Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Helix Design

3480 views
7 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    April 2003
  • 305,205 posts
Helix Design
Posted by Anonymous on Thursday, December 4, 2003 5:54 PM
Our club is building two layouts. One N scale and one HO scale. both will be multi (bi-level) level layouts. We intend to utilize helixes to transverse from one level to the next and back. A couple of questions come to mind that we would like to get answers to in order to help us ensure we do everything a well as they can be done. 1. What is the minimum spacing between tracks in a helix (we will be utilizing a double track main line around the entrie layouts and helixes. Normal HO spacing is 2 -1/2 centers. (I am not sure what it is for N scale, as I am involved mainly with HO)? 2. What is the minimum radius of the curves in the helix that is recommended for use (we have some 85 ft reight cars and double stack container trains)? 3. What is the best recommend grade percentage (we are shooting for around 1.9-2.2 percent)? 4. What is the best loop spacing for both HO and N scale (based on the total distance btween the top of the rails on one level to the top of the rails on the next level up the loop or after one complete loop travel)?5. With a multi-level layout, what is a recommend distance (hieght) between the two levels (we are shooting for about 24 inches)?

The alst question really doesn't concern helixes. We are planning on building many of our own turnouts. We are trying to locate PCB ties or blank PCB (copper cladded boards). Where is a good place to look? In the event we must make our own ties, what thickness and tyupe of PCB material shuld we use. I've seen Series 600 (Presensitized) and Series 500 (regualr). I've seen single sided cladding, 1/16 -1/32 - 1/64th inch thicknesses. Which is best?

I would greatly appreciarte any help you folks can provide.

Our entire layout will be DCC utilizing a Digitrax Radio Equipped Super Chief Sytstem with several boosters and PM42's as well as track detection.


thankyou,

  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Friday, December 5, 2003 9:52 PM
An often loved, and often maligned topic.

First, MRP had a great article on helix deign (check out '96 or '97). John Armstrong's book on Track Planning is great. Search for helix on this site in the forums, there is a plethora of information. Also, check out the Guage website and railway forum. More than you need to know, some redundant, some superfluous, but overall, good background and helpful information. Good luck.
  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Wednesday, December 10, 2003 2:26 PM
Thanks for the info. Was able to find out the answers to most of the questions, thanks to a lot of the members of this and other forum sites (Guage, Atlas, etc).

Still trying to verifying n-scale track spcing (center to center) within the helix. It appears that the 2-1/2" spacing for HO layouts (standard) will also work throughout the HO helix. I suppose that I can just take the ratio of HO to N scale (87/120) and multiply it times the HO helix clearance measurements and track spacing. That should keep u in the 'ball park'. The best percent grade or maximum recommended percent grade varies heavily between members of the various forums as many of them were really 'restricted' on space. We have a minor space restriction, but not 'horrible'. We would like to find the best percent grade without taking up too much space. It would be great to have a 0.5 to 1.0 percent grade, but it probably isn't necessary to achieve good operations and therefor the exceess use of space would be wasted', greatly reducing walkway space and layot space.

thanks

  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Wednesday, December 10, 2003 3:39 PM
I have a large "ho" scale layout and utilize the helix operation a couple of different applications. My layout is multi-level, 4 levels, and the best operating in helix is 3" centers allowing the 85' passenger cars. Also my raidus is no less than 28, thus allowing me to best utilize the space. My incline is a full 3% and I have no problem pulling a 30' train through with two power units.
  • Member since
    January 2002
  • 1,132 posts
Posted by jrbarney on Wednesday, December 10, 2003 7:18 PM
nsdra1,
To answer your last question, about PC ties, you might want to try Clover House. They offer them in four different scales. Their URL is:
<http://www.cloverhouse.com/>
Hope this helps.
Bob
"Time flies like an arrow - fruit flies like a banana." "In wine there is wisdom. In beer there is strength. In water there is bacteria." --German proverb
  • Member since
    September 2003
  • From: Near Zurich, Switzerland
  • 50 posts
Posted by Rene Luethi on Friday, December 19, 2003 11:36 AM
nsdra1,

I have a suggestion for the PCB ties. I needed some 5000 PCB ties and thus, the price was a serious factor. I went to a PCB manufacturer in the hope to see what PCB materials are around, and from where is it obtainable. I left this factory whit a sheet of this stuff in the same thickness what the wooden ties have which I use. The sheet had the size of a tabletop. With this sheet I went to a factory that is specialized to high-pressure water-cutting. They sliced this sheet in strips of the same wide like the wooden ties. When I am in need of a new bunch of ties, I clamp a side-cutter to the workbench and with a piece of scrap wood and a second clamp I make a stop. Then I shove a PCB-strip through the open cutter to the stop and close the cutter and I have the first tie. Open the clamp, shove the strip, and close the clamp . . . After half an hour I have a hurting hand and end this session. But I have enough ties for the next months of track lying
Good luck and merry Christmas.
Rene.
  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Monday, January 5, 2004 2:19 PM
I was reading in one of the magazine articles about track spacing in N scale. They said that the 2-1/2" spacing used in HO would be acceptable for N as well, or maybe just a shade less. The biggest problem is being able to get your fingers into the space so that you can lift a car off the track if necessary, without knocking over the adjoining cars, especially if you're in a yard.
  • Member since
    April 2003
  • 305,205 posts
Posted by Anonymous on Monday, January 5, 2004 5:57 PM
For HO height, if you have your HO NMRA gauge, and make it higher than the little points on the top you will be able to run everything, with the gauge standing on the bottom track. Same with N scale and the NMRA gauge. Better to be a tad to high than a tad to low. Who knows, 20 years from now you might have guys wanting to run AutoMaxs and the like.

I have 20 inches of separation between levels and I find that works fine. But what I suggest is get some cardboard and mock up what you are thinking about at the widest point the two levels will be - to see the tunnel effect. You can do this in about 10 minutes or less with a friend. You will learn more about your plans doing this than anything we can write in a forum. When I did it, I discovered I needed more separation than what I had planned.

Remember the more track in a helix, the longer you won't see trains and have to wait for them. You'll be amazed at how long a train will seem to disappear in a 24 inch separated helix. At a 2% grade, that is roughly 96 to 100 feet of track (not double tracked). So in separation you need as much as you need and not an inch more.

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!