Finally! We Get To Draw Something!

"Its ok to have a bowl of spaghetti as long as it has purpose! I'm not going to get around to scenery, anyway."
- Pedro

Ok, I know all of you out there in TV land have already started sketching stuff on graph paper, but I wanted you to know that careful planning UP FRONT yields to much easier on paper designing. We know our purpose, our parameters, our industries (business) and our trackage. Now we just have to shove it in a box on the CAD system.

So let's get started!

First, we'll discuss the track. We are going to use Code 83" Peco or Micro Engineering track, whichever we can get cheaper. The Peco track has more narrow ties so we'll design it for ME track. The limited square footage of the layout has us using small Porter locomotives and very small rolling stock, so we can use very tight radius turns. For our design we'll call 18" radius a minimum.

"WHAT!" you say? Oh, you must be an HO guy. "We don't use 18" for HO and you want to use it for O scale!" Actually yes. The On30 combination is very nimble and the Porters can run on track that is 12" in diamter! Even my big three truck shay runs easily on 18" radius.

The Design

You can do one of two things: start with a box and put the track plan in it, or start with a track plan and build the box around it. For this layout, let's combine the two approaches.

We are going from the plains of Mexico to the 2,000 ft mountains. I'm thinking a lot of grades here. Just like HO, On30 only pulls well at 2% to 2.5% grades. This means to achieve any elevation we are going to have to nest several over and under loops to get any great height. The problem with this is that the bowl of spaghetti winds its way up the mountain, but will need even more spaghetti to get back down to town. Better make a lot of meatballs!

In this case, we'd normally use a point to point design, just like the prototype. However, we have to go back to our guidelines list where it says that it must have a continuous loop for display purposes. Crap! What are we going to do now?

Ok, first of all it is a GUIDELINE, not an ABSOLUTE. The purpose of the guideline is to show trains running on the layout. Well, a loop to loop design does that, doesn't it? Hmmm. It will limit us to using a DCC system with a reversing port, but we can do that. We'd probably want to use DCC anyway. Ok, loop to loop it is! We can always pretend the loops aren't there for operations and we can get away with not putting turntables on the layout which are expensive and hard to maintain.

That means we need a loop at each town/mine and the trackage to wind up the mountain.

Before we do anything, let's go change our string diagram...

Be sure to update your diagrams and charts as you proceed that way Kalmbach will be able to keep track of your mess when they publish your layout. Right. Well, I keep hoping!

So let's get the CAD system going and layout some circles. We want to put the two main loops in first.

While this is not meant to be a lesson in CAD drawing, I will share with you some things that I do to help me keep organized. First, you have to set up the drawing. Knowing that I want the railroad to fit in an area no bigger than a small bedroom, I've set up the drawing grid to be 12 feet by 12 feet. I've set the grid to be 12" main squares with 3" minor divisions. The name of the layout design will be Peñoles Mining Company in On30 Layout 1.01 with the last digit changing. I keep ALL of the revisions as you never know when you might mess up.

Nothing but potential! Let's get the two loops in there. I'm going to use HO scale track sections for this since On30 is not available. If it is and you know about it, would you send me the file!
Here are two 20" radius circles. They probably need to be bigger than that, though. If our minimum radius is 18" and we have to put another circle on the outside, then we need a 21" radius, which is a 3" distance from track center to track center as used in On30. Because of our parameters we are most likely going to end up with a waterwings design.
Here is the full loop with a turnout, stretched to 23" radius with a Peco turnout. Wow! Its big. We aren't going to get much track on this layout...unless! He he he....I've got some ideas.
Ok, so they look like ta-ta's. These are loops in a waterwings type design. Wow, they are very close together in the middle. For those of you that don't know me I'm the poster child for mirth and girth. Essentially I have a 24" right of way because I'm a big hefty. So the tightest point on the layout aisle can't be less than 24". We want to keep the layout small, so how do we get around this without moving the "blobs" out?
In order to widen the gap you just slide the blobs! Notice I've made another "layer" in the CAD system called People and I made a round & fat "Scott Perry" gauge. I'll keep it around to make sure that I can fit in the aisles.

Our next job, Mr. Engineer, is to figure out how to get from the plains to the higher elevation. This is going to mean some really winding track. That means one of the blobs is going to be up on top! Uh oh. We better make it the minimum radius then.

Here we have the two main loops: 23" and 18" and then two additional loops that we will need to gain elevation. Looking good! Don't worry about it looking toyish as we'll bury some of those loops in solid rock.

The blob on the right was leaned into toward the aisle to broaden the curve out of the turnout. When you connect the loops you get a preliminary track plan that looks like this. Not bad for right out of the gate. For some of you it may be hard to understand it at this point, especially without elevation marks. Basically we are looking at a climb of about 14 to 16" from the zero point (larger of the loops). Cool! There will be three mountain peaks, one for each loop and another at the bend of all the curves. The long suspension bridge will go across the straight track in the aisle. Still don't get it? Don't worry...we are still in the early stages.

Write your comments and questions below!