Maximum Grade


maczimb

Member
I asked the question before but no one responded.
What is the maximum recomended grade for HO. I had heard that one should not excede 4%???
Today I talked to a guy who claims to be something of an expert model trainer.
He said that he always recomended 1% to 2% maximum?? This seems a bit extreme, at 2% I would need to have a bench top about 17'-0" long, to have a line cross over another, assuming I would need about 4" clearance for a train to pass under.
This same guy said that I should use paper mache over chicken mesh for any landscaping I do??
Help.
Mac
 
Well, joke as you may, but he is about right. 2-2.5% (max) is what most try to limit their grades to. The steeper the grade, the less traction of your loco = fewer cars in your train. If the grade includes a curve, then the % is even smaller. You can get by with a steep grade with only a couple of cars, i.e. unloading ramps, etc. Lots of luck with a 4%...even with traction tires.

Paper mache w/screen wire was and is used quite a bit, but most prefer plaster soaked towels or plaster gauze over a cardboard weave for the base of scenery.
 
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Rex is absolutely correct, and the fellow you were talking to was being kind, passing on good advice. However, the fact is that many of us learn to compromise so that we can have a layout...at all. We also learn tricks of the trade. If a 17' run to get 2% and sufficient rise is out of the question, split the difference. Rise for 8.5', but also have the rails to be passed over drop to the overpass and then climb back out again. Happens in the real world, too.
 
Modeling grades accurately can be difficult, especially due to space concerns. When I built my first layout I put quarter/half inch styrene risers every so often under my roadbed, it gave the tracks a sort of "rolling" look like you see on the prototype.

By the sounds of it, you will need to make your grade a bit steeper to get over the other line. Alternatively you could always keep the above line at the same level, and just have it grade-separated by that much throughout the layout. Would save a lot of trouble in the long run.

Of course, on the prototype I've seen ridiculously steep grades on industrial sidings and on interchange tracks.
 
Grades

Hi Guys.
I was not trying to be funny, I was genually surprised at his answers.
My thanks for clearing up the questions, and thanks for the advise.
I guess I will have to rethink my proposed layout, as soon as I get the hang of the XTRAX cad system.
Can't wait till I get home to Arizona and away from yjis hurricane prone city.
Mac
 
Mac, hang in there. Where there is a will there is a way and we will help you try to figure it out, if you want. ;) :)
 
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Mac, Selector had some good advice about how to handle a grade where you need to pass over something that can be dropped below tabletop level. You can end up with two sets of 2% grades this way instead of a 4% grade. Believe me, although 4% doesn't sound like much more than 2%, it really is. It's the difference between a normal length train with two units having to pull the grade slower than on the flat and a train half the size with either four units up front or mid-train or end of train pushers. Even 2% is nothing to sneeze at but 4% starts to present real operating problems.
 
On a past N scale layout I had a 4+% grade and on a curve! I had a 30 car trains make it but it took 3 units up front to power it up and made dang sure the heavest cars were in the lead........Never again will I have 4% grades! You can make trains do it but it puts a real strain on the locomotives! If you don't have the room for 2% or less change your track plan!
 
You have recived good advice so far
I have a grade on my layout that is about 4% I run short trains,9-12 40' freight cars max!. I can get away with the grade but When I start pulling 19-22 cars with light engines or steam with no traction tires I start to slip

My steam with traction tires and 6 axel diesels does better on the grade.

As mentioned above if you can split the grade into 2 diffrent points on the layout you will be able to pull longer trains up the grade. I did this on the other end of my layout and never have any issues there.

Trent
 



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