What I would Do

Yes I would use a helix if it worked for my case.

I would make a quick and dirty helix with a 14" radius and 2% grade.  Up on the outside down on the inside.  Run trains.  See what works. weight your cars.  Watch your vertical curves and easements.  For DC locos use analog volt and amp meters to monitor performance on the helix  I use a 20 Volt volt meter and a 1.5 amp amp meter from China.  Got them off ebay.  For DCC use a RRampMeter V 3 to monitor performance. 

You will have problems.  Record your successes and problems on your thread.  We will give you great feedback on your successes and help you with your problems.

Mike Lee

Quick and Dirty Helix

That sounds like a plan - I could make one up - go up two laps and see how my engines perform.   I think I'd build it to the same standard as the finished product would be so that if it works, I just keep going up more laps, if not, well I have a fire pit in need of more wood. 

The Helix would be limited to DCC.  in my layout plan my DC track circles the outside of the layout.  Goal is to make it not appear distinct, but isolated from the DCC line.  (have pondered whether a level crossing would work with one line DC and the other DCC but decided to pass due to the risk of shorts).  

RE Testing the loads with a RRampMeter ... never have done the meter thing or worried about monitoring volts etc.  have to look into that whole side of MRRing.  

The plan evolves

Getting the hang of XtrackCAD - lots to learn for sure, but it is coming along. 

https://flic.kr/p/MSJ8V2

Hoping this link to my Flicker post works.  if it does not will have to go back and see what I can find on how to post via flickr.  

I'm really leaning towards keeping it on one level.  In part because the base level will be 50" off the floor already.  The upper deck if built would require stepping stools or stilts.  

And there is something to be said for K.I.S.S.ing  

And wholly bankroll Batman, those helix's will chew up the track budget real fast.  A double tracked 13 & 14.5" R helix has almost as much track as the rest of my layout.  

So, I've been pretending to be a CAD technician and playing with XtrackCAD.  Reading past issues of MRH and other magazines and books I have, watching MRR Youtubes and browsing websites - there is not shortage of materials.  

In the plan that I hope you can see, the mainline has a min. R of 16" - yes wish it was wider but I'm working in an alcove 76" wide so there are limitations.  Choosing a lift bridge to allow for continuous helped eliminate the tight tight curves in my earlier plans.  Sure a lift bridge (or duck under bridge) is a compromise but in my case it made sense.  

There is a bit of a helix of sort - more of a once around loop to climb 2.5"  in smaller space.  

That same spot where the lower track climbs that 2.5" to connect with the higher track, could be used to helix up 12" if I did want to 'take it to the next level' - so that still could happen.  .... but today I'm more inclined to just keep it on the level - one level (more or less, track level ranges from 50 to 53" off the floor).  

Helix

If you go to two levels you have to leave enough room above the upper tracks on the lower to clear the bottom of the upper level.  If the helix goes up 12 in, the upper tracks on the lower level are 2.5" above the base, that leaves 9.5 in of clearance.  Throw in at least 2 in for the thickness of the upper shelf, you are down to 7.5" clearance.

Lighting two levels also becomes a consideration, especially maintaining light levels between a room lighted portion and the portion under the upper shelf.  If light level is important to you its something you will have to consider.

I would suggest looking at your yard design, it looks like the maximum size train you can easily run, based on the runaround length, seems a bit short.

Consider double deck without a helix

One deck for longer running, the other deck for branch-line, industrial, junction, etc.

There is no rule requiring a helix and the associated fabrication/costs. A long continuous run where the train is hidden in a helix is certainly a compromise. It has a place for some schemes but is not a given.

I use stacked staging. Since I do prototype ops, trains bound for the lower branch line deck enter staging on the upper deck. They re-appear on the lower deck staging the next session to continue their run. Trains are moved by hand between sessions.

All depends on how many trains and how long they are whether you might need a helix or not.

Developing Track Plan

Decided to pass on the a multi level layout.  As it is, this layout is an ambitious project for me.  I'm more interested in create scenes than operations.  It is designed for single operator but one guest could also play. 

Getting the hang of XtrackCAD (took some effort but well worth the it). 

Questions and suggestions welcome.

Construction of the benchwork started this weekend.   

Track is Peco 55 using older Peco 80 switches (plus an old Shinohara crossover I'm rebuilding - it needed a lot of TLC).  The Shadow Box will be my waterfront scene and will be removable, ... maybe even take to a show some year.  The top of my helix will be "Santa's Village" park complete with a Z scale park train.  It too will be removable.  It will also tilt up over the helix.  It is a small helix, one loop goes down 2", and two lines go up 2".    This layout will have one full loop running DC elecally isolated (it is the inner loop that runs around the layout).  The trolley and Z scale are also DC.  All the rest of the track is DCC (NCE Powercab).  

FKD

I have a helix that works great,

I have a helix that works great, it is 48"x48" and is cut from one piece of wood.

http://www.rslaserkits.com/CVR/Files/MR-Quarry_Helix.pdf

It is built like a quarry.