Okay, I have been doing some thinking and came up with a couple of ideas for my layout. My table size is limited by spacew constrictions of wall and space in the apartment. so where I can not go out I will try to go up.
If I put 12" between the two levels, how long (in inches please) would my sloping track have to be in order to maintain a 1-2% grade. Thinking of putting a staging track/ sorting yard below and maybe a loop to give trains longer run time.
Thanks for the help in advance.
A 2% grade will give you one inch rise in 50 inches forward. For a 12 inch rise at 2% grade, just multiply 50 inches by 12 and you need to go forward 600 inches (50 feet). An old trick to lay out an aprox 2% grade is to take a 2 foot level and tape a 1/2 inch shim to one end. Keep the shim at the lower end of the grade and the bubble will center when you have the 2% grade. A 1% grade is a one inch rise in 100 inches forward, which is the 1 to 100 ratio to make this a percentage.
For a 1% grade: It’s 1" of rise for every 100" (or 8’-4") of run; 2%: 2" for every 100", and so on. So, if you want a 1% grade to climb 12", you’ll need 1,200" (or 100’) of track. 1/2 that for 2% grade (50’). 1/3 that for 3% (33.3’).
Here’s a handy site: http://www.urbaneagle.com/data/RRgrades.html
Tom
And that stark reality ought to make clear why so many of us lesser mortals with small layouts resort to 3% grades. Even if we only want to elevate our track so that we can run trains over a lower track with about 3.5" of vertical separation for a bridge deck, we have to climb quickly in the space we can afford.
THis seems to be the case do to layout constrictions.
Dead minimum, 612 inches.
Don’t forget the transitions.
1 to 2% huh?
You need a bigger room, house or shop.
Or go to 3% and buy additional engines for helper service.
Some folks rely on a Helix, round and round straight up.
Boy, can people make things complicated!
The first post specified a height difference of 12 inches, aka 1 foot.
1% grade = 1/100 = 100 foot run [:O]
2% grade = 2/100 = 1/50 = 50 foot run [:(]
3% grade = 3/100 = 1/33.3… = 33 foot run [:-^]
Note that the distance may be a straight line, line with a loop (Tehachapi style,) sidewinder track, pretzel shape (don’t laugh - I have one) or simple spiral with or without short tangents between the end curves to keep the grade from going astronomical.
Note also that the length of run makes no allowance for a vertical curve to ease into and out of the grade. Rough cut - add 1 foot of run per percent of grade.
A 24 inch radius spiral will gain 3 3/4 inches on a sustained 2.5% grade - good for reasonable overhead clearance if you use a thin subgrade. Widen it (or lengthen the laps by making them oval) and the grade can be reduced. Tighten it and you’ll have to run Shays or install a rack (Mount Washington style.)
Chuck (modeling Central Japan in September, 1964)
Thanks again to you, Chuck!
You have a way to turn the “@$)(*%(%” into “%)%*()$@” by “simplifying the mustard” that we many times seem to inject into our layout planning. Your explaination is going to be placed into some of the layout spirals I am currently planning.
Keep up the insight & perspective!
I don’t understand, Chuck. Can you be more specific? I thought that we had covered the question pretty well. He specified restricted space, a loop, and 12" of rise, but mostly he wanted the distance in inches to yield that rise. We gave him the three common grades to help him to visualize it.
Maybe I am missing something.
This is what Texas Zepher drew out for me. I am wondering inf I can squeeze a small staging yard and helix under the main layout?