I would like to start my layout but I need help. I’m looking for plans for a double Helix in HO scale with the inter track 22 radius next track 24 Something that I might be able to down load and possible print out. I’m fairly good at wood working so I just need the first piece to make a pattern. thanks J
On YouTube search under “model trains helix plan” your will find more then you need.
What’s so hard. LIONS don’t need no stinkin’ plans!
You need a piece of wood and a saw. How hard can that be.
This helix (a four track mane lion) is built from some scrap OSB board that I found in the wood shop.
Tracks are laid directly on the wood, why make the train climb an extra 1/2 inch! The table, a former heavy weight ping pong table allows a loop 5’ in diameter: figure 28, 26, 24, and 22" radius curves. LION runs 50’ subway cars, so this is ok on all tracks.
If you want to run big 85’ cars up your helix, I’d want to make it 7 feet in diameter as a Minimum, 8’ would look better.
In the original configuration, there was no helix… would you believe that this worked with most of my trains.
First Helix (only 2 tracks…)
Inside the new helix tunnel…
A couple of thoughts. Unless you are running very short trains of short cars, that radius will probably be much too tight. Many experienced modelers have found that a minimum of a 26" to a 28" radius will more reliable for typical trains in HO.
In addition, for any longer cars and engines, 2" separation between concentric 22"/24" curves in HO will likely prove to be too tight to avoid sideswiping, let alone in a demanding helix arrangement.
Tight curves add substantially to the effective grade of the helix, which creates a real danger of string-lining (derailing across the center of the curve) for typical trains.
One little ‘trick’ that seems to go unnoticed at first - the critical bit for getting the proper grade is the very first layer. After that, the height of the spacers between levels is exactly the same, to maintain a steady grade.
The other thing often missed by first time helix builders is - you need to lay the track as you go, it’s nearly impossible to get in and lay the track between levels after the whole framework is built.
–Randy
Rule of thumb is the radius should be 3x the length of your longest car. Even then, wheel flange drag can be an issue when you have an 86’ car tied to a 40’ car. See Jan 2009 Model Railroad Hobbyist magazine for details; great article. http://model-railroad-hobbyist.com/magazine/back-issues
Dan
Oh My! My cars are 50’ long so you are telling me that my helix must have 150’ radius! Gee… the room is only 24’ wide~
ROAR
Math fail. An HO scale 50’ car is just under 7" long. Times 3 is 21 inch radius.
In any case, subway cars, which are relatively short, of a consistent length, and (often) each one powered, are a completely different situation than the typical locomotive-drawn train of mixed-length cars that the Original Poster is asking about.
I will have you know that the LION got a 17% on his algebra final.
OK, him got a B on college algebra, but that was after him mastered English Grammar.
21 inch radius? Well, no wonder they work so reliably. LIONS like reliable railroads.
ROAR
I don’t know if this book is still in print. The Model Railroading Handbook by Robert Schleicher. A Chilton Book.
I shows how to build a helix using two radius. 24" and 28" radius with a straight section making the helix oval in shape.
There was an article in MR a while back with Jim Hediger building a helix. I mostly followed his approach when building the helix on my layout. As previously stated, the two major tricks to building a helix is getting the grade of the first level as accurate as possible and laying track as you go. Once the first level is complete, just use identical height spacer blocks to build the remainder of the helix.
One thing I did differently from others was using two layers of 3/16" plywood laminated together to fabricate the curved subroadbed. This resulted in a helix consisting of 3/8" plywood with lap joints where single pieces of 3/16" plywood butted together (no additional space-robbing lap blocks were needed). Adding spacer blocks about every 45 degrees with wood glue resulted in a structure that is extremely strong and rigid. Similar results could be achieved using straight lengths of plywood with angle cut ends. Just stagger the joints between the two plywood layers to ensure strong lap joints result.
In order for your trains to operate well, you want as little deviation in the track radius and grade throughout the helix. Thus, make sure the grade is constant from top to bottom of the helix and draw track centerlines on the subroadbed pieces to ensure you can accurately line up the plywood pieces as well as locate the track on the plywood.
My plywood lamination technique meant my helix construction was slow since I let the glue of each helix level cure overnight before continuing on the next level (I used a lot of spring clamps gluing up each level). Once the glue had cured, I laid the track on the finished level then constructed the next level. At this point, I allowed the glue to cure overnight, and so on for 4.5 levels. Set aside at least the same number of days/evenings as your helix has levels if you want to do it this way.
AWK! who is going to go through all that work.
HELIX of LION works just fine.
Here is a guy selling Helix kits on ebay, but you can see from the photos how it is made. Not that hard to do, just layout on large sheet of paper/cardboard and get your template for all 1/4 segments. Go to his store for more detailed photos.
-Bob
http://www.ebay.com/itm/360748748605?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649