Trix Big Boy Traction

[Anonymous]

Just a question for all you UP Big Boy owners........ I have a Trix Big Boy and find that it's pulling power on the flat is unbelievable, 50 cars or more is no problem. However, I have a section on my layout with a 4% grade and the Big Boy can only pull 4 NMRA weighted cars without slipping and finally stalling with wheels spinning about halfway up, no matter what speed I try, even with a running start at full throttle! (It is a curving grade with 22" radius about 6 feet in length total)

My Rivarossi Challenger (newer model with can motor) can pull 16 cars up the same grade at any speed without slipping once. I realize that the Riv has traction tires, but it weighs less than half the Big Boy.

Track & wheels are clean, no oil residues, etc. Any ideas? Help please!

[cacole]

I had a very similar experience with a Lionel Challenger, which probably weighs almost as much as the Trix Big Boy. The problem was the coating on the locomotive drivers that was applied at the factory. When new, the Lionel wouldn't pull five cars up a 2 percent grade without slipping. After the coating wore off of the drive wheels, it pulls 20 or more cars up the same grade.

Make sure your track is clean and doesn't have an oily film on it, and chean the locomotive's wheels, too. Then run it through a break-in period of a couple of hours and see if traction doesn't improve.

[rrinker]

To be honest here, a 4% grade on a 22" radius curve for such a huge locomotive... the equivalent grade for that, because of the tight curvature, is going to be a LOT more than 4%. Perhaps even double. One cannot expect a lot of pulling power up a 6-8% grade!

[railman]

well, any way you shake the box, you'd like to see a big boy pull more than four cars!

[Anonymous]

Thanks for the info on the grade and curvature, equates into quite a climb. But it still seems strange that my Riv will out pull the Trix on a hill. Even when my Riv's traction tires were worn out (have been since replaced) it would still pull ten cars up the hill.

All my cars are free rolling, metal wheels. The one thing I have found though is, the Big Boy will pull 4 Riv 85' passenger cars up the grade quite well at higher speed. These are the new design cars with the body mount couplers, working diaphrams and are lighted. Quite a bit heavier than the freight cars. Weird......

Too bad the Big Boys didn't pull passenger trains.... But it is my railroad, perhaps???

[Anonymous]

Just a thought. Could the wheels be coming off the track due to the long wheelbase and the steepness of you grade?

[Anonymous]

Another idea - something I've heard of when converting a Hornby 9F 2-10-0 steamer to loco drive (as delivered, they're tender drive, but there's a company that will mill a slot in the frames and install a motor in the loco). I recall reading an article by the designer of the conversion in which he explained the work involved. He found that the converted loco had a similar problem to begin with, in this case as the lead 2-wheel truck was rubbing against the mainframe and lifting the lead driving wheels off the rails when climbing grades - might be worth checking if this is the case.

[twhite]

I know that the Trux Big Boy is supposed to take a 22" radius, but I wonder if, like Railroad--Brit says, if that 4-wheel lead truck is doing a number on your cylinders? Remember, the Allegheny has a shorter wheelbase and a 2-wheel leading truck. I still worry about the 4% and 22" radius and 6' climb combined. Is there a way that you might be able to re-lay the track into a 24" radius instead? Believe me, two inches of radius in HO makes all the difference in the world, and with a 24" you can be assured that most of the modern long-wheelbased steamers are manufactured to take it with ease. As to using Big Boy on passenger trains--hey, guy, it's YOUR railroad and nobody elses! If I can use my Missabe Yellowstones to pull PFE reefer blocks over the Sierra Nevada, you can sure use your Big Boy on a passenger run. That's what makes model railroading so INVENTIVE! Best of luck, but I'd really take a look at relaying that curve to 24"
Tom