I need a little practical help with easements. I understand the reason for easements and it all makes sense to me. However, when it comes time to draw the centerlines for laying my track, I am lost. I have read Armstrong’s “Track Planning for Realistic Operations” and still don’t get it. I subscribed to Video Plus and wasn’t able to find anything there. If anyone is so inclined, could you give post a simple approach to planning and laying an easement. For what it is worth, I am trying to accomplish this using Peco C55 flex track (n scale, obviously.) My goal is to lay an easement into a 12.5" radius curve.
One more thing. I am using AnyRail to plan my layout. I have read the user guide relating to it’s support for easements. Once again, I just didn’t understand it.
An easement curve is just like a regular curve except larger.
I’ve only done about 6, but I start with about 2" larger radius, then start 2->4" back from the end of the original curve (I’m working HO, so half these numbers for N/Z) I then draw the larger radius circle till it intersects with the original curve. I then smooth out the point where the curves intersect.
Just using a larger radius fixed radius curve leading tot he main curve is often enough. It’s not a true easement, but it reduces the “coefficient of lurch” as diagrammed in Armstrong.
To make a decreasing radius spiral, it’s really not that hard. You need something flexible like a piece of molding or furring strip. When you lay things out, you’ll see in Armstrong where he mentions having the tangent (straight) part centerline offset slightly outside of where it normally would fall if you just had the continuous radius curve. You then secure part of this strip along the centerline of the tangent, and bend the other end in to intersect the radius of the fixed part of the curve. This will form a naturel decreasing radius curve leading fromt he straight to the actual curve. There’s your centerline for the easement. This is the “bent stick” method mentioned by Armstrong. All the magic happens because if you take an object that naturally is straight, and bend it only at the ends, and letting the middle freely choose its curve, it will naturally form an eased curve. Not sure about Pecos N scale track, but their HO code 83 does this,; Atlas HO code 83 flex track even more so will naturally form an easment if I fasten down the straigh part and them swing the end into the desired curve centerline. The free part in the middle will have a decreasing radius from straight up to the point where it is curved to the actual curve radius, so I’ve never plotted out the centerlines for an easement like that. Cork roadbed will also form an automatic easement, again so long as you first attach the straight and then the curve but leave the in-between free until each end is fixed.
This will not help you in drawing your trackplan in your software, but when it comes to drawing them on the roadbed I use the bend stick method. I offset my tangent track from the end of the actual radius curve by 3/8" (I work in N scale as well, so these are actual numbers). then I measure back from where the tangent and curve would have met 6" and I measure into the curve 6". I use a strip of nominal 1" lumber ripped down to about 1/8" thick. I lay this stick on edge on the tangent line and tack nails on each side of it to hold it from moving side to side, the last mail being at that 6" mark on the tangent. I then bend the stick until it crosses into the original curve at the 6" mark I made on the curve and use more nails to tack it into place. Finally I use a pencil and trace along the stick, giving me a nice smooth transition from tangent to my radial curve. This method was spelled out in an old issue of MR (probably more than once). I wlll look up the assue tonight is you want and post it here. Hope this helps. I know picutures would probably be more helpful.
No, you’re absolutely correct, as far as you said. Easement track gradually transitions from tangent (straight) track of NO radius to a curve of some set radius (defined by you). In AnyRail, the Easement Flex feature creates a piece of track with a given degree of curvature (an arc of a circle) which is straight at one end and terminates in a curve of a given radius at the other. You can’t directly set the length of the track – the software calculates how long it has to be to do what you said.
I’ll admit that I’ve been using AnyRail since version 3.something, so I’m probably better than the average bear. With that caveat, doing easement flex in AnyRail couldn’t be easier, as long as you know what you’re trying to do (As with all “layout planning” software, the software only facilitates the process, it doestn’t actually do the planning for you). So, take a deep breath, say to yourself, “I can do this,” and follow the procedure below. I’m assuming you have the latest version of AnyRail.
Let’s say that we’re going to make a 90 degree curve at 24" radius.
Click on “Settings” in the menu bar About midway across the Settings ribbon is a category called “Flex”. Leave “Alert on Flex too Long” and “Alert on too Sharp Curves” checked off. Below that it says “Minimum Radius”. This shoudl be set to the value you’ve identified as the minimum acceptable curve radius for your layout. It defaults to 36, so if you tried to create an easement with a radius less than that, it would tell you “Value out of bounds” (and I’ll grant that a more specific error message would be useful there). For this example, make sure it’s set to 24" or less.
Insert 2 lengths of flextrack of your desired brand.
Right click on the first, select “Curve Flex” and in the dialog box, type
If you are not using track planning software and you want to draw a easement track centerline on the sub-roadbed without doing any math or actual draftsman style gyrations there is a rude and crude backwoods method.
Tie a string to a pencil.
Wrap the string around something round and large, garbage can lid for example.
Tape the non-pencil end of the string to the lid.
Place the pencil point on the tangent track, pull string tight by moving and/or rotating garbage can lid.
Lift pencil and place point on end of curve, note slack in string.
Move/rotate garbage can lid until pencil can be placed on both points with a taunt string on both. This is a hit or miss affair that may require many movements of the garbage can lid to find the sweet spot.
Once the spot is found draw the line from tangent to curve. The string winding around the garbage can lid as you draw will create a perfect natural easement because the length of string is changing while the centerpoint is not.
If you draw from tangent to curve the string should wind, if you draw from curve to tangent the string should unwind.
Note the string length and relative garbage can position. It will be similar for the other easements you draw thus reducing the time spent finding the sweet spot.
Like I said, it is rude-n-crude but it works swell.
Base on what I read in http://www.anyrail.com/help_en/flex.htm an easement flex section is fairly easy, go with 15 degrees and the radius you need. Left and right set the straight vs. curved sections. You will need a curved flex section of identical radius to extend the curve past 30 degrees, i.e., a 60 degree section.
This is analogous to the same command in WinRail (except there you can specifiy the angel for the entire curve).
Easments are a matter of give and take. If you want an easment to run your railroad through the living room (for example) you may have give up a little somewhere else.
I just use Ribbon Rail Metal Track Alignment Gauges to make sure that the radius of each curve is not less than 32". That way, I have no problems with derailments or unintended uncouplings.
Do you really need to be concerned with easements except where your curves are really tight, say less than 24" radius?
For operation, it’s probably more important to avoid kinks than to worry about easements when your curves are fairly broad. But IMO, long steam engines and passenger cars just look better when there’s an easement. I’m sure others will disagree, and that’s fine.
Sort of. I am till relatively confused, but ask anyone that knows me and they will tell you, this is to be expected. I figure I just need to try and see what happens. I think I will use AnyRail to diagram the easement, print it out full-scale, and use it as a template. My goal is to learn and, hopefully lessen my confusion. That is next weekend’s project.
Solder two lengths of flex, or what you need of two lengths to make the distance around your curve to tangent again. Attach the two ends to what exists for tangent ends on either end of the curve. Anchor the joints with several screws or nails so those joints cannot budge.
In the very center of the curve, push the tracks outward, away from the centerpoint of the curve, a distance of 0.5". Fix the tracks there with a couple of nails. You now have your eased curve. It’s a close approximation, and will do nicely.
To add to the good advise already given here is how I do my easements, but scaled down to N.
What I’d suggest that you grab pencil and paper, draw it full size, and see if it both suits your purpose, and looks right to you. I would also add that when it comes to the actual track laying, BEWARE of KINKS.
In my opinion Rich, along with super elevation, just a matter of personal aesthetics.
