Did you mean lower level at 48"?

You said UPPER level at 48".  That is pretty low for an upper level.  Your lower level would be somewhere around 30" and that is too low to operate while standing.  Unless you're unusually short.  If you meant lower level at 48", then your upper level could be a little closer than 18".  Best bet is probably do make a mock-up using cardboard or shelves or whatever you have, and simulate your two levels and see how you like how it looks to you.  

Randy

aceptable seperation distance between a bi-level N scale layout?

 I think it depends on the width of the benchwork,the type of scenery on the lower level, and the construction method and how that affects the thickness of the upper level benchwork. for shelves 24 inches wide I'd guess something like 18 inches would be desirable. for 12 inch wide shelves probably 12 inches separation would be fine? As suggested above I'd do a mock up of possible  heights using various  benchwork widths and see how they look to you as everyone has their own preferences for viewing angle.....DaveB 

Several things to think about.

No matter your scale, deck seperation comes into play for the actual construction. I have a short section that it 12 inches between decks. I found it tight to actually build and gave up some visual effect too.

Most all of my other deck areas was 16 inches seperation and this seemed to look better as well as easier to build.

Just getting your head in the shelf to sight down the track during installation was tough. Drilling holes, installing lighting, etc you need room to work.

As for grade, 3% is pretty steep.

what I did

First in your helix area of 4 by 8 I would highly recommend a nolix instead.  A nolix is a modified helix which isn't circular with an agenda of have some of the track visible and sceniced. I'll show you two pics, one of my main layout and one of the nolix.  Trains disappear for too long in a traditional helix, by having some of the track visible, the "wait" isn't as unbearable.

My nolix is roughly 2.2 % grade, and in your area you should have a suitable amount of room to run at 2.2 or lower.

What you will be seeing is four loops, but unlike a helix which has loop over the next loop, no loop is identical to the loop above it.  On my nolix the first loop won't be visible, the second and third loop will be visible from the front only, but roughly 20 feet of visible and sceniced track out of roughly 75 feet of track.  My curves are approximately 17 1/2.  Realize the photo of the nolix is taken with a quite wide angle lens so there is distortion in apparent height between the loops, so the roller coaster effect isn't as dramatic in real life:

Inside of the nolix:

This next photo I jury rigged to show people how I am going to scenic the area, just a rough idea as I found many weren't understanding the visible bit about track you can see:

And here is a pic of the two levels, roughly 38 inches for the bottom level and 57 1/2: [You can just see the tops of the L shaped brackets I made to hold the upper level]

And finally a rough outline of the bench work shape, the curvy area is the nolix:

Benchwork height video

I agree wholeheartedly I'm 5' 6" tall and 48"-50" is at armpit level. So! A 48" to 50" top deck sounds just right. BTW I'm 68 years old and having to stand on a ladder or footstool to operate my own model railroad is rather ludicrous.

A 16" separation would give me a lower deck height of 32" which will allow me to use my computer chair with plenty of knee room.

not a helix but a nolix.

A nolix! I was thinking of something along that line but didn't know the term. Any hints on construction would be helpful. What is the separation between levels on the nolix? What is the horizontal separation between the back of the lower visible track on the nolix and the front of the track on the grade above it?  I guess I'll have to tone down the pitch of the "nolix" to about a 2% grade.

To all: Thanks for your replies. They were very helpful.

Stretching out the helix.....

...into an oval shape will help but you need to remember that grades on curves are tougher on locos because of the friction involved so a grade on a curve has to be "compensated".  In other words while the math may say you have a 2% grade, for example,  the grade will be effectively greater than 2%  because of the curves.  How tight the radius of the curve is will determine how much the grade needs to be compensated. There is a table or formula somewhere  that you can figure this all out with.

I'm no expert and I may be wrong but I never thought that just stretching out a helix meant it was a "nolix" I always thought of a "nolix" as a long ramp that traversed the whole layout space gradually making the climb from one level to the next.

MIchael

I always thought of a "nolix" as a long ramp

yeah ,that's the common usage of the term. A 4 by 8 helix would be more of a  circular challenged helix or something :> ) ......DaveB

Separation isn't scale dependent

because its your height and your viewing angles that matter.

I think a lower deck height of 24" would probably uncomfortably low -- 6" lower than a standard desk.

If you want to stand while operating on both decks you'll likely need to raise the upper deck to get more visibility (and construction clearance) for the lower one.

A mock up is a good idea. Maybe a mandatory idea. Don't forget to mock up the thickness of the upper deck. If you plan valleys or canyons in the upper deck scenery, remember those will protrude downward. If you want mountains on the lower deck, they will protrude upward.

Also think about how far you can reach into the lower deck for construction and scenery. Remember that if the track isn't along the front edge of the layout, having a industrial spur behind an industry can be very frustrating when trying to couple or uncouple cars. Ditto for manual switch controls -- a Tortoise starts seeming worth the cost when you can't see the turnout.

Keeping the lower deck narrow helps. Remember, with that deck above you can't use your "helicopter" to look behind things.

A double deck layout gives you a (sometimes much) longer run than a single deck but it comes at a cost -- visibility and access for construction and maintenance. Speaking of which, you didn't mention the size of your space. If the helix becomes a significant portion of your space, you may spend lots of time going in circles on hidden track to get to the next level with a relatively small amount of visible (modeled) track. Only you can decide what ratio of helix to visible track is acceptible.

If you have a moderately large space, a nolix is definitely something to consider. To determine if making the layout itself be an around-the-room-helix figure out the length of the track in each lap of the room. Subtract space for towns and switching areas which have to be level. Then see if you can achieve enough elevation change to get to the next deck using reasonable grades. A mountain railroad might have some steep grades, say up to 3%. But if you're modeling Kansas, a lot of 3% grade is going to feel really strange. In general, the longer each lap is, the easier it is to use a nolix.  Another thing about a nolix, once you've gone all the way up, either you turn the train and descend -- a pure point to point configuration, perhaps with dual staging areas, top and bottom. Or you add in that helix to connect the top to the bottom for a continuous run.

Sounds like you're going to have a lot of fun with your new layout. Good luck!

Charlie

I'm not going to go into a

I'm not going to go into a long dissertation here, but John Armstrong invented the term Nolix as a joke for a chap who commissioned him to create a layout without a helix; John's first proposal had three helix's, so the client was firm and stated "no helix."  If you can find a copy of the Athabasca layout I believe in roughly 1998 you will see a track plan with a peninsula as an open "stretch helix" sceniced area that John humorously called a "nolix" for no helix.

I moderated a layout design forum for a number of years and it was then I introduced the term nolix as a useful term to describe an area that acts like a helix to gain height, but it isn't a round slinky like helix.  This was over ten years ago.

In the 2014 Great Model Railroads on page 13, you will find the layout created by Gerry Albers has an area he calls a stretched helix, which is what I would call a nolix.  I can link folks to a longer thread I did on nolix development.  By the way, I'm not saying I invented areas that aren't helix's in terms of construction, what I have tried to do is create a vocabulary that allows us to be clearer about what a layout design feature is that isn't a helix but gains elevation.  If you turn to page 13 you will see an area called Maben which is what I would also call a nolix.

Grades on a curve:  A nolix is better than a helix as usually there are sections of straight track as can be found on page 13 of the mag discussed above, or if you look at my nolix.  So in a helix the train is always going in a circle so more stress on the wheels which increases the "effective" grade.  On my helix there are only certain areas where the train is going through curves.

I am reluctant to give you my measurements because one of the problems with a nolix is they are all "one of a kind" so what I do will be different than what you do.  The separation is determined by the shape of the area you a creating a nolix in; so in my area, I think the nolix is about 6 1/2 long where as yours will be 8 feet long.  I was originally going to do 3 loops around but the grade would have been too steep.  With yours even if you did something like what I have done, you should be below 2.2 grade.

I'm a modern era freak so I want to have my trains with multiple lash ups of engines, once I throw on two SD90's onto my train length of roughly 9 feet, up the train goes.

I have made my nolix area to roughly reflect an area in British Columbia called the Thompson canyon (railfans usually glop the Fraser and Thompson river canyons under one moniker, the Fraser Canyon).

So what I did will be different from what you do, and how you construct it will be different from how I did it possibly. The last thing you need to know is that I am a lousy carpenter but I still was able to build what I did on my own design.  I did have help but initially my help had trouble understanding what it was I was trying to do.  So my recommendation is that when you get to building the nolix, have a white board ready to show what it is you are trying to do probably to a guy who is very familiar with helix's but has no clue as to what a nolix is.

Lastly I'm willing to help you out if you decide to go in the direction of a nolix.  Is the 8 foot long section going to be the visible length, or will the nolix be 8 feet deep and 4 feet wide but only the 4 feet will be visible?

And one lesson I did learn, and heed this advise, build the bottom deck, then the nolix, then the top deck.  I built the bottom and top deck, then had to try and find a grade that would work.  When you build the top deck, you can create it to meet the end of the nolix run up.

Cheers.

you want mountains on the lower deck, they will protrude upward

which means separation is partially scale dependent?    N scale redwoods and  water towers are a lot shorter than O scale redwoods and water towers. Reaching over an N scale train takes less headroom  than reaching over an O scale train.  Width of benchwork is quite important when figuring out layout levels for satisfactory viewing and access but the width of benchwork is also scale dependent, a 7 track yard is a lot wider in O scale than in N scale....DaveB

To rsn48:     Thanks for the

To rsn48:     Thanks for the reply. 4' deep about 7' +/- wide. The wall length is 9'6". I'll have to take a door and temporary wall out to extend one side to 16'.(I built a bedroom for my eldest son in the basement. He has recently moved out) the layout will be (4'x9'6") x (2'x11') x (2'x16'). that's left wall, forward wall, right wall. I may have to blossom out the end of the right wall for a return loop. The elongated helix / nolex will be on the left wall. I was thinking to decrease the depth of the nolix at a couple of levels to show a train traversing across the face of the mountain on a ledge.

I was traveling East on PA rte.22 near Gallitzin, PA when I spotted a train up on a mountain, quite a ways up the mountain. It came out of the Allegheny tunnel and was in the Sugar Run Gap (2% down grade) heading towards the Horseshoe Curve. Damn near wrecked my car when I saw it. Couldn't stop to take a photo. This inspired the nolix.

As I said....

I could be wrong about the definition of what a "nolix" is.  I was just going by the context in which I had seen the term used. At any rate, it's interesting to know that John Armstrong coined the term. I did not know the origin and history of it.  Whatever you call it and whether or not you stretch it out into an oval shape or not there will still be some curves that have to be accounted for and compensated for when figuring the effective grade. You can't get around that.  Personally I'm not a fan of helixes in any form and I'm not all that enamored with multi deck layouts. I just don't care for how they look with the exception of the mushroom types because you can't see both decks at once.  I just commented because I've always built mountain layouts and I've been dealing with grades probably from the first layout I ever built and I've learned quite a lot about them over the years.

Michael

don't care for how they look with the exception of the mushroom

A lot of the appeal of double level layouts comes from seeing them in tightly cropped magazine photos where the two decks in close proximity are not shown. Go see one in person and it's not usually as attractive as the two decks and the less than ideal viewing heights become fully apparent. I'd build a double deck layout if that was the only way to fit in what I wanted but I'd try to design a mushroom first and a single level layout before that......DaveB

Don't know how to PM here so.....

I can't figure out how to send a personal message, PM, so I'll give you my "public" email and if you contact me there, I'll help you out rather than drag this thread out.

can_rsn_48@hotmail.com 

To me "nolix" means "no helix"...

I think the term "nolix" is a contraction of "no helix" which means there is no helix, not an oval helix, a stretched helix, a modified helix, or any other type of helix.  A nolix layout climbs from one deck to another without the use of a helix of any type, but rather by using a nearly continuous grade throughout the entire run.  There is no helix; stretched, oval, kidney, or otherwise.  

Randy

Since I invented the idea of using the concept Nolix

It obvious folks aren't reading posts earlier in the thread, but what follows is a long post I did at Nscale discussing the concept:

Well Lee, thanks for the vote of confidence.  First some history.  Back in roughly 2000 I had read the article of an Armstrong plan Jim Money's Athabaska RR in the 1998 edition of MODEL RAILROAD PLANNING.  In it Money recruited Armstrong to create a layout plan and was adamant he didn't want a helix, he was so adamant that Armstrong drew up an initial plan with three helix's.  Jim asked John to draw up another plan doing away with helix's which Armstrong did.  Armstrong in a moment of humour decided to call the "place" (not the thing) a nolix for no helix.  

Also in roughly 2000 I became the moderator of the layout design forum at Trainboard which I was part of for roughly five years.  Since the forum was my suggestion and the other moderator added to that forum quite after three months, I was basically on my own.  The independence gave me a public forum for ideas which influenced others.  The idea I flogged the most, particularly for N scaler's was the idea of a nolix.  

When I read the Planning article of Money's Athabaska RR, I decided the word "nolix" was useful to the hobby; we had a word to describe a "standardized" circular incline to move trains from level to level, but we didn't have a word for non-standardized construction to move trains from level to level.  What also became apparent to me when looking at Armstrong's plan was the trains were visible, much more than in any helix with a window or what have you, and the visible area was incorporated into the scenery.  So I decided - "a nolix was a non-standardized helix with the purpose of moving trains from one level to another creating as much visibility of trains as possible, incorporating these visible areas into the scenery." 

I then preached this concept near and far, from Model Railroader mag to the Atlas forum, to obviously the Trainboard layout design forum, the layout design sig, etc.  The problem for me was that helix's tend to be a large blob with not much sceniking options, pretty much a big circular mountain.  In N scale because of our lesser requirements for "broad" curves, you could have a peninsula only 40 inches wide and you could have a nolix, or a corner area such as I have used and have a nolix.  The peninsula that Armstrong created for Money was very large as you can imagine it would have to be in HO.

I became inactive in the hobby with severe hobby burnout, all my activities on the net (being moderator and an active participant, particularly on the Atlas forum) died out, and with medical problems I kind of drifted away from the scene.  Currently I am seriously playing with the idea of writing an article on "Nolix's" for one of the RR mags.

Where I have changed over the years is that I have decided the word nolix by itself isn't that useful; the reason being is that if I say helix, because of its standardization, we can visualize one.  But, if I say nolix, because it is not standardized, visualizing one is difficult.  Or in your case Lee, what you have visualized is different than what I produced thus helping back up my assumption that the word nolix needs to be expanded.

So my conclusion is that other words need to be paired with nolix for us to get a better idea of its usage.  So if I say Lee has a "peninsula nolix" we can draw some rough conclusions about it in our head, if I say Rick has an L shaped nolix we can have a better understanding of nolix, or again I can say Bill has an around the walls nolix, and we understand the concept.

So do I have a nolix, I say yes, this from the guy who made the word popular.

Secondly does it dip and dive, not really as I worked with a friend who has built his own helix and we used some "helix" technology to maintain grade "consistency."  The grade is roughly 2.2 % though in one two areas slightly less, and in a straight run, a bit more.  Realize that a 2.2 % grade in my nolix will have less "stress" on the wheel/rail contact than in a helix as the train isn't consistently going "round and round."

Here is a link to me talking about the concept of a nolix at Trainboard back in 2002 when I was a moderator there:

http://www.trainboard.com/grapevine/showthread.php?68709-Another-Nolix-(track-plan)

Here is me talking and Andy Sperandeo responding in a thread in the Model RR forum, back in 2002:

http://cs.trains.com/mrr/f/88/t/3517.aspx

The road run is firmer than it looks, there are still some areas that will get bracing, and the plywood has been aged.  

There is 19 3/4 inches of separation from the my layouts first deck to the second deck.

And here is another pic, in the background you'll see a level with the one end boosted, used to maintain a consistent grade through the nolix, harder than with a helix:

Would not the be just real big helix you stand inside?

No, A Nolix was created to get away from a helix of any form. A helix spirals up in layers either symmetrical or non symmetrical while a Nolix is a non repeating snaking route that gains elevation as it wanders around the room. If the room was small and the route around it took more than one lap you could call it a helix I guess but normally a Nolix gains the elevation without repeating the pattern so a round the room layout is not usually a helix. ......DaveB

Further Reading...

"Here is me talking and Andy Sperandeo responding in a thread in the Model RR forum, back in 2002:

http://cs.trains.com/mrr/f/88/t/3517.aspx"

Byron Henderson's explanation (several posts below Andy Sperandeo's) is the commonly accepted meaning of the term "nolix" - perhaps a misinterpreted by the masses from John Armstrong's original idea - has nevertheless been burned into MRR lexicon and defined closer to what Byron described in his post. Thus, and with all due respect, the image you posted is of a helix (albeit kidney bean shaped, but still a twisted curve in a relatively small space in relation to the layout) and not a nolix. This even if you have interpreted John Armstrong's original term correctly, which was a stab at humor rather than the definition of a design element. It would appear that the majority have boarded another ship and sailed in a different direction than yours.

Back to the OP, and as others have indicated, deck separation (rail top to rail top) will depend on the height of the upper deck and the height of the viewer (you). This is assuming that your layout doesn't have any drastic scenery elevations (cliffs, rivers, cuts, etc.), so let's just further assume that the decks are level along the axis of the track. Note that works for me or others may not work for you.

The higher the upper deck, the less separation that is needed for the lower deck. I too model in N Scale, and found that with my 6'-2" frame that 42" (hip height) would be the minimum for a lower deck, and the an upper deck height no more than 60" (armpit) if I wanted to do any switching moves. This is with two decks with a depth of 24" and a separation of 18". I'm personally willing to increase the upper level height if there isn't any switching involved without help (ie: stepstool). Same goes for the bottom shelf - I'm willing to decrease the height a few inches if it makes for a better and more comfortable layout overall. Reduce shelf depth to 18", and with the lower deck at your hip or waist level, you can squeeze the decks to 15" or maybe to 12", thus lowering the upper deck. However, if your railroad is set in mountainous territory, you may need to increase the separation a few inches to compensate for the amount of scenery otherwise out of your view on the lower level.

The best way to visualize how things might look to you is to set a few shelves at varying heights and place a couple of small boxes or building models you might have, perhaps even with a locomotive or a couple of freight cars to mockup a small scene. If you envision deep cuts and hilly or mountainous terrain, than use cardboard taped in place to further conceptualize a given area. Depending on how things look to you, you may decide to narrow or broaden a shelf or increase/decrease the distance between one level and the other.

Don't forget about the fascia, as this will remove some of the viewable area on the lower shelf (usually 4"~6"), and/or make sitting and operating the lower shelf uncomfortable. Also note that when adding an additional deck to your layout that you must also consider aisle width. What passes as an acceptable aisle for a single-level may prove claustrophobic with a multi-deck design.

Cheers!
Marc - Riverside

The 1994 Athabaska RR

The 1994 Athabaska RR (Model Railroad Handbook N0. 44 - 20 Custom Designed Track Plans by John Armstrong) is indeed a multilevel design.  The main level is at approx. 50 inches, the upper deck at approx. 70 and the lowest level (what J.A. called "secluded track") is at 47 inches. This was to accomodate an eye level of 65 inches (that's about 5ft 11 height) and two duck-unders at 64 and 72 inches respectively.
His general rule of thumb on deck separation was 14 to 20 inches for practicality and convincing scenery (hidden staging levels only need about 7 inches for access).

As to what is a "nolix", an oval helix is still a helix. A no-helix is a single incline that doesn't have overlap of levels.

LoL, this is funny.  Trust me

LoL, this is funny.  Trust me it was me who developed the term, John Armstrong had no intention of the term being used as a thing, it was a location on the layout.  The reason I put that long post with links was to show you how far back I had been talking about it, but if you are keen, I am lazy go to Trainboard and do a search on Nolix and you will see I had been talking about it for over a decade.  And I'm writing an article right now on the idea, just not sure whether to submit it here or N Scale mag who seems desperate for material. 

A helix is standardized, you can buy one from a manufacture you can find advertising in MR, you will never see a nolix advertised as it isn't standardized; each one is its own unique self, unless some one copies a track plan incorporating one from some one else's layout.  A helix is slinky shaped a nolix isn't; mine isn't.

I just got unlazy and went to Trainboard and got one of the early times I was talking about nolix's, I dug this up at Trainboard and the date on this post is May 22, 2001.  This is one of the first times I was telling another in the hobby about it, I had just been a moderator in the layout Design forum there for a couple of months at that point:

May 22, 2001: [I had just designed and mailed out a track plan to this person back then and was responding to some of his queries about it]

By the way, the lay out plans I sent you contained a "non-helix, helix." I couldn't send you an example because I couldn't find any. Yankinoz sent me an example from the magazine - Model Railraod Planning 1998 p.34. John Armstrong designed it (the grandpappy of layout design) and he jokingly called it a "nolix" - based on a pun of no helix. This is the only example I can think of to show you. Area 4 on the plans I sent you contain the "nolix." John Armstron based his nolix on around a 20 inch seperation of deck heights. I didn't know this at the time I was planning my layout.

Helix Photo

Unless I completely misunderstood your comments, the image posted below is a kidney-shaped helix (a continuous turning spiral used to gain elevation, be it round, oval or otherwise). The (to be completed) partially viewed scenes shown would be akin to a tiger without stripes. The cat is still a tiger and the photo is still of a helix regardless of your claims to the contrary, credentials, or liberal usage of the term "nolix".

FWIW, the CSXT Shenandoah track plan from one of your earliest posts completely reverses its direction and is a prime example of the commonly accepted use of the term nolix, whereas the shape in your photo merely curves a bit here or there, but never completely reverses itself within the spiral's footprint and therefore is a helix.

As I indicated in my previous post, the accepted use of the term nolix is what Byron Henderson described in his response to your post on Trains.com. Generally speaking, and without intending to credit Mr. Henderson over anyone else, especially yourself, the concept has since been burned into the model railroader mindset. This may have not been your plan, but it is what it is.

Thanks for playing.

Cheers!
Marc - Riverside

without intending to credit Mr. Henderson over anyone else

Armstrong seems to have made it perfectly clear when he labeled that first nolix location on a layout that a nolix is not a helix in any form?......DaveB

Armstrong's design

Exactly!  Armstrong designated a location not thing, just like I live in Deep Cove, which is both deep and a cove, but Deep Cove isn't a thing but a location.

If "how many understand it" is used as an argument, I can continue in this vain, remember no one has talked and written about nolix's more than me.  

Pete Nolan - the chap who makes ships and maritime goodies for the hobby - joined Trainboard after I became moderator there and took hold of my idea, but roughly a year or so after he joined and began discussing nolix's, I ended up with some medical issues and severe hobby burnout and wasn't that active as in the early days.  So Pete's concept of a nolix is an around the walls deal, so many - when they correct me - remind me a nolix means only something around the wall.

So if you have actually been doing your homework and read all of this thread you will see I have moved from saying just a "nolix" but have decided for accuracy to include a second word.  So a nolix can be an L nolix, an oval nolix, a kidney shaped nolix, a V shaped nolix, a peninsula nolix, an around the walls nolix; all of these designations indicate the structure is not standardized like a helix.

The reason I pursued this concept and have flogged it for well over a decade is to add precision to the conversation, the purpose of words anyway.  So I could say - "Bob, I know you are considering a helix in that area, but if you extend it some, you could have an oval nolix and some of the track could be sceniked to add interest to the area."  

So that is why I push the idea, because not only does it help to discuss a track plan but it helps in track planning itself.  So the guy could think, ""now what should I put in there a helix or a nolix, now a helix takes up less space but its a giant blob, or I could use more space to open some of the track as part of the scenery.....hmmm. A helix is easier to build, everyone knows what it is, a nolix I have to plan on my own....hmmm.  Or I could just purchase a helix, and forget all the problems of nolix construction."

That's why you have to loosen your mind up about what a nolix is, its pretty much anything that gains elevation without being a helix.  Now I know how Barrow's felt when he introduced dominoes layout design and construction.

By the way, if you go to many forums around, you will see some of them running "layout parties," I invented that; again if you go to Trainboard you will see I started them off, it was a way to get people enthused about their layout if they hadn't been building it and a way to encourage non-Trainboard members to join Trainboard and become active there.  Then N Gauge copied the idea and ran them, and now I see them around various other forums, such as N Scale.