True Maximum Grade for Garden Trains (8% possible?)

[dieseldan]

Hey folks,
I've read that you should try to keep your grades to 3%.
My brother is working on his layout this weekend and is attempting to create an 8% grade. He's tested it and with 3 cars it looks like his locos can do it!

Will his engines "wear out" quicker with this kind of climbing?

Thanks,
Dan Sherman

[Matthew (OV)]

Certainly the harder you make something work, the more chance there is something will break.  But .... it all depends on how you approach the problem.  In recent memory, there was a story about someone being told that pulling more than a very low number of cars was dangerous, as it was outside the design spec and would void the warranty .....  the same locomotive has been seen pulling trains of more than ten times the length specified with no visible harmful effects.

So....

Can you pull a train on an 8% grade?  Probably.  It'll look more like a roller coaster ... and you'll be very limited in the number of cars you can pull... but you can do it.  Would you want to do it for hours every day, like on a display layout running continuously?  Probably not.  And, you'd want to make sure you kept up with lubrication, maintenance, and kept track of wear on critical parts, etc. so that when something did start to wear out you could be prepared.  That's not bad advice even for non-extreme railroading.

Operationally speaking, it might make sense depending on the type of train involved.  Cass Scenic does it with the real thing every day of the week, and their grade is somewhere between 10 and 11 percent.  But ... in the real world, most "normal" trains would see 2% as excessive.... I'm told by one of the crews at Cass that their 45 ton diesel, when it was functional, could barely make it up the grade to Whittaker running light.... whether or not the end of that locomotive's operational days was brought about by being made to do this is anyone's guess.

Does that help?

Matthew (OV)

[Kevin Strong]

8% can be done, but it's certainly not recommended practice. My dad's got a short section (around 20' or so) of 8% grade on his railroad, and short trains have little trouble going up. But up is only half of the equation. Going down is another story. Depending on how the gearing is designed, some locomotives are subject to surging when going down steep grades. This happens when the weight of the train works to push the train forward faster than the motor is turning the gears. This causes the locomotive to stutter (stop abruptly, then move again, then stop agin...) This constant stuttering is not good on gears, bearings, or other mechanical components.

If you keep things under 4%, you'll be fine. Anything more than that, and you begin to really limit your train length and significantly increase the effects of the aforementioned surging. We don't see it on the 4% grades, but we do on the 5% and above.

Later,

K