What grade do you all find the most tolerable? I realize that a lot depends on the engine and consist. But I’m, thinking 7%, any comments?
Also, graded curves I know this can be tricky but trying to some up with some vertical space. Considering a below layout reversing loop.
Thanks for any thoughts…
Whoa !!! 7%…
That could create some real problems for the locos and control. It would also impact the length and type of your consist.
I would say 4% or less, the smaller the better. If you are looking for an upper level lower level transition would you have space for a helix ?
Most real RR only use 2% as a max. I try not to exceed 3.5 %.
7% would be doom, even 4% is a tretch. I used 2% and there is really no effort in the climb, although the descent has some speed to it.
Easy forumlae for figuring -approximate:
1/2" rise for every 12" of run = 4%
3/8" rise for every 12" of run = 3%
1/4" rise for every 12" of run = 2%
I needed to close teh gap on a four inch height difference between tracks. Four inches at 2% would take 16 feet, so I had one track descend while one track ascended, which cut teh amount of run I needed in half., as shown below:
I use 4%, and it goes around O-31 curves.
4% really slows down my traditional Lionel diesel with traction tires pulling 5 passenger cars (with lit interiors). It can do it, but to keep the same speed it has on flats, the voltage needs to be increased on the uphill grade.
On the whole curves aren’t a problem, but you need to pay attention to the voltage on the down side or the train will go off the curves.
You can find a voltage where it will run well on flats, will take a while to climb the grade but will do it, and zip down the down hill grade without flying off the curves.
Does this ring a bell with anyone… I thought I read an article a number of years ago in either CTT or OGR about something called an “offset helix” for use in mountains layouts where space was limited but a quick rise was needed?
7% grade is crazy. I tried this once and had loco’s that would slip and spin their wheels and numerous coupler failings with attendent breakaway cars racing down the grade to derail ro cause other problems.
You can make a reasonble sloped helix with O-72 if you intend to run modern scale equipment. You can get away with O-54 if you stick to semi-scale. The formula for the circumferance of a circle is pi times the diamter. Pi is close to three so you can guestimate the length of a loop by multiplyng the rated diameter by 3, e.g. O-54, 3X54=162. A 1% grade on an O-54 loop would get you 1.6 " rise, a 2% grade 3.2". Don’t forget that when doing the calculation that you need to measure from the top of the rail on the lower part of the loop to the bottom of the ties/supports on the section of track you are crossing. This is your actual clearance. This also applies to any support structure you are using to support the helix.
Multi-level layouts are visially interesting but you may want to ask yourself whether you want to actually try and run trains from one level to another as opposed to seperate eleveated tracks. Grades eat up a lot of real estate.
I don’t know what I was thinking, I really didn’t mean 7% [D)][D)][D)]
I just got back from Santa Barbara, got confused coming down the hill.
Blame it on this strange weather Don. [:D]
I don’t know, sometimes I amaze my self, oh well. It’s colder than a witches -it in a brass bra. Hope it is warmer next week in SD. Oh year, should I bring down the cab forward with me?
4% max, 2% comfortable.
This helix is 2% and works great. a good modern engine can easily pull 40 modern cars up it.
As Chuck mentioned, a helix has a critical dimension. That is the height gained per loop. I used 8" rail top to rail top. In order to get 2% grade, the helix is 10’ diameter. I run all modern equipment, so the height is important. I have the square footage to dovote to this monster.
Don’t bring it, I’ll give you my Cab-1 and you can run mine. [^]
Doug, I was refferring to the Cab Forward Engine, runs on O-72, the one Lionel had out last years catalog. 32" long.
Great topic! I learned a lot here.
I use 4% which is basically what the 110 trestle set creates. I also have to use a lower voltage setting on the down except for my dual motored 2354 F3. This can climb and decend at the same voltage. Although the descent is a little faster than I’d like.
Now, my new aerotrain with cruise goes up and down beatifully at the same voltage and it’s cool to watch the engine brake on the down.
I love postwar but cruise is truly cool.
Mike S.