I've seen some discussion related to easements and I think I understand "theoretically" how they should be done, but I'm wondering if I can simplify things by using the approach in this image. Basically I'm suggesting a 30" radius (pseudo) easement into a 22" radius curve. Any thoughts?
Yes, the 30" radius in front of the 22" radius provides some easement. But why do that to yourself? Are you using sectional track that has a 30" radius piece? There are easier ways to construct a "near spiral" easement.
If drawing by hand, allow for a 22.5" radius and 5"-6" of straight where it connects to the 22" radius curve. Don't worry about using easements at turnouts unless you are hand-laying track.
If using the Atlas RTS software, use flex track in place of the last section of 22" radius curve. Again, offset the joining straight track 1/2" outward and 5"-6".
Other software generally has provisions for inserting easements.
When laying out the actual track, use the "bent stick" technique, or use the "springy" Arlas flex track and replace the last section of 22" radius sectional track with flex track.
just my thoughts, your choices
Fred W
Take a piece of paper, maybe tape two end-to-end so that you have a total length of something like 22-24". One one side of the seam (in other words, on one of the sheets), in the centre of the sheet, draw a 30" radius arc that begins at one end of this longer sheet and ends where you have the new seam between the two smaller ones.
Now draw a 22" arc on the other side of the seam, on the other sheet, and join it to the first arc right at the seam...make sure they are thin lines that just touch.
Now, in good light, turn this large sheet so that you can look at it from one end, and get your head down low and about one foot away from that paper end so that you get the best view. Look at what you have created. That is the "easement" that you are going to create. IMO, it is hardly worth the effort. It looks terrible, and you will not have created anything useful for all the effort and expense.
Use flextrack, instead, fix one end to the end of the last tangent section, buttress both with some nails outside of the rails for a length of about 1" on each side of the join, and then bend the flex to conform to the average radius of curvature that you will want it to adopt so that it meets the tangent end on the other side of your required curve. It will do it all for you.
Here's how I would do it. Fasten the one end and buttress it as I said with nails. Hand flex the segment so that it lines up nicely (eyeballing is fine) with the other tangent's end. Keeping it all in place and flat, use a marker to make dots where nails could be placed at the inner rail base along the apex of the curve. Let the segment straighten, drive in a longish and sturdy nail or two, and then re-bend and align the segment. You would hope that it lies tight against the nail(s)...and that would be highly desireable. Assuming you are happy with what you see, mark and cut the rails to be joined, and slip joiners onto them. Re-bend and fasten them to the tangent, but this time you will need to provide supporting nails to those two joins as you did on the other end. Place some full soup tins on their sides and onto the rails to keep it all in place. You could solder the ends, use track nails, or glue the ties as you wish. The point is that you can get good alignments at each end with method and get a reasonable approximation of a useful easement. So much cheaper than buying section segments, and the function is variable and more physically realistic.
My
Thanks all for the comments. Fred, is this what you are suggesting?. . . .
Jambam,
Your drawing is exactly the way I form easements - and have for 33 years (I first used that technique in late 1973.) I only have one thing to say for it.
It works!
Chuck (modeling Central Japan in September, 1964 - with spiral easements)
Thanks everyone for the help. Chuck, I'm assuming you're referring to the most recent sketch that I sent, right?
Thanks.
jambam wrote: Thanks all for the comments. Fred, is this what you are suggesting?. . . .
As Chuck said, you are good to go. The second diagram is exactly what I was describing.
Fred Wright