I think I may be able to keep the grade increase limited to the straight run but if not this is information I will keep in mind. My trains will just be short for now but over time I imagine that will change. I will try to plan accordingly. Thank you
Figuring grade..
- Thread starter Goldnut
- Start date
I think I may be able to keep the grade increase limited to the straight run but if not this is information I will keep in mind. My trains will just be short for now but over time I imagine that will change. I will try to plan accordingly. Thank you
The calculation here isn't particularly difficult, you get roughly 98.96" per 90 degrees of curve. So, over the course of 90 degrees, .9 inches is roughly 1 percent increase in grade. So, if you keep it to no more than 2.5 inches of rise, you'd be within the 2.5% grade window for that portion of the track.
EDIT: That's for the 63" radius. For the 72" radius, the formula is 2*pi*72 * .25 so, 113" or so, so about 1 1/8 inch for a percent increase in grade.
Alcomotive
Grandson of an ALCO Builder
Selector
Well-Known Member
Not on engine size, but on traction. Our scale locomotives have a surprising amount of power, so power is almost never a problem, even on steep hills. The real problem is traction. If you hold a locomotive down tight to the rails with something like another pound or two over its own weight, and dial up the voltage or speed steps, it will almost certainly spin its drivers. But that's just it....it spins. The same thing happens on grades.
I predict you will find that, with a compensated grade (meaning with curve) of 6%, your locomotive will barely be able to get itself up the slope. It and one or two properly weighted and free-rolling cars.
M
MHinLA
Guest
Goldnut, I don't know where this 6% grade stuff is coming from..Please explain .. We've spelled out the dangers of 3% or more..You seemed to have gotten that...Then you lay the 6% thing on us.. What on earth are you yappin' about ?! Where's the logic in that ?!
This will be my final reply to this thread..It's gotten insane !
This will be my final reply to this thread..It's gotten insane !
Please take the time to read all the YAPPIN I have done through this post and you may find out that I said I will try to stay within the 2-2.5% grade. I do believe that someone else mentioned 6%. Not I.
I really do appreciate all your help though.
Robots_walk_the_earth
Active Member
I tossed in the 6%... I did some quick figuring for the N scale layout I’m planning. I was thinking I need to rise 3” in 60” of track with a 13” radius. But I think I can work with that to make the numbers a bit more favorable. Sorry for kind of hijacking the thread.
jdetray
Well-Known Member
The Grade Calculators on my web site (mention by Burlington Bob in Post #6) use equations that take into account the difference between straight grades and curved grades. The equations for curved grades in both HO and N-scale were empirically derived by model railroaders, including John Allen and John Armstrong, who actually measured the effort required to pull trains up curved grades as compared to pulling trains up straight grades.
- Jeff
- Jeff
